diff --git a/modules/openapi-generator/src/main/resources/csharp/libraries/generichost/JsonConverter.mustache b/modules/openapi-generator/src/main/resources/csharp/libraries/generichost/JsonConverter.mustache
index 7948f79dbf7c..456f4635013c 100644
--- a/modules/openapi-generator/src/main/resources/csharp/libraries/generichost/JsonConverter.mustache
+++ b/modules/openapi-generator/src/main/resources/csharp/libraries/generichost/JsonConverter.mustache
@@ -43,8 +43,25 @@
             {{#lambda.trimLineBreaks}}
             int currentDepth = utf8JsonReader.CurrentDepth;
 
+            {{#composedSchemas.oneOf}}
+            {{#-first}}
+            bool oneOfHasPrimitiveType = false;
+            {{/-first}}
+            {{#isPrimitiveType}}
+            oneOfHasPrimitiveType = true;
+            {{/isPrimitiveType}}
+            {{#-last}}
+
+            if (!oneOfHasPrimitiveType &&
+                utf8JsonReader.TokenType != JsonTokenType.StartObject &&
+                utf8JsonReader.TokenType != JsonTokenType.StartArray)
+                throw new JsonException();
+            {{/-last}}
+            {{/composedSchemas.oneOf}}
+            {{^composedSchemas.oneOf}}
             if (utf8JsonReader.TokenType != JsonTokenType.StartObject && utf8JsonReader.TokenType != JsonTokenType.StartArray)
                 throw new JsonException();
+            {{/composedSchemas.oneOf}}
 
             JsonTokenType startingTokenType = utf8JsonReader.TokenType;
 
@@ -113,24 +130,40 @@
             {{{datatypeWithEnum}}}{{nrt?}}{{^nrt}}{{#vendorExtensions.x-is-value-type}}?{{/vendorExtensions.x-is-value-type}}{{/nrt}} {{#lambda.camelcase_sanitize_param}}{{name}}{{/lambda.camelcase_sanitize_param}} = default;
             {{#-last}}
 
-            Utf8JsonReader utf8JsonReaderOneOf = utf8JsonReader;
-            while (utf8JsonReaderOneOf.Read())
-            {
-                if (startingTokenType == JsonTokenType.StartObject && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndObject && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
-                    break;
 
-                if (startingTokenType == JsonTokenType.StartArray && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndArray && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
-                    break;
+            if (oneOfHasPrimitiveType &&
+                startingTokenType != JsonTokenType.StartObject &&
+                startingTokenType != JsonTokenType.StartArray)
+            {
+                {{#oneOf}}
+                Utf8JsonReader utf8JsonReader{{name}} = utf8JsonReader;
+                ClientUtils.TryDeserialize<{{{datatypeWithEnum}}}{{nrt?}}{{^nrt}}{{#vendorExtensions.x-is-value-type}}?{{/vendorExtensions.x-is-value-type}}{{/nrt}}>(ref utf8JsonReader{{name}}, jsonSerializerOptions, out {{#lambda.camelcase_sanitize_param}}{{name}}{{/lambda.camelcase_sanitize_param}});
+                {{^-last}}
 
-                if (utf8JsonReaderOneOf.TokenType == JsonTokenType.PropertyName && currentDepth == utf8JsonReaderOneOf.CurrentDepth - 1)
+                {{/-last}}
+                {{/oneOf}}
+            }
+            else
+            {
+                Utf8JsonReader utf8JsonReaderOneOf = utf8JsonReader;
+                while (utf8JsonReaderOneOf.Read())
                 {
-                    {{#oneOf}}
-                    Utf8JsonReader utf8JsonReader{{name}} = utf8JsonReader;
-                    ClientUtils.TryDeserialize<{{{datatypeWithEnum}}}{{nrt?}}{{^nrt}}{{#vendorExtensions.x-is-value-type}}?{{/vendorExtensions.x-is-value-type}}{{/nrt}}>(ref utf8JsonReader{{name}}, jsonSerializerOptions, out {{#lambda.camelcase_sanitize_param}}{{name}}{{/lambda.camelcase_sanitize_param}});
-                    {{^-last}}
+                    if (startingTokenType == JsonTokenType.StartObject && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndObject && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
+                        break;
 
-                    {{/-last}}
-                    {{/oneOf}}
+                    if (startingTokenType == JsonTokenType.StartArray && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndArray && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
+                        break;
+
+                    if (utf8JsonReaderOneOf.TokenType == JsonTokenType.PropertyName && currentDepth == utf8JsonReaderOneOf.CurrentDepth - 1)
+                    {
+                        {{#oneOf}}
+                        Utf8JsonReader utf8JsonReader{{name}} = utf8JsonReader;
+                        ClientUtils.TryDeserialize<{{{datatypeWithEnum}}}{{nrt?}}{{^nrt}}{{#vendorExtensions.x-is-value-type}}?{{/vendorExtensions.x-is-value-type}}{{/nrt}}>(ref utf8JsonReader{{name}}, jsonSerializerOptions, out {{#lambda.camelcase_sanitize_param}}{{name}}{{/lambda.camelcase_sanitize_param}});
+                        {{^-last}}
+
+                        {{/-last}}
+                        {{/oneOf}}
+                    }
                 }
             }
             {{/-last}}
@@ -376,7 +409,51 @@
 
             {{/children}}
             {{/discriminator}}
+            {{^model.discriminator}}
+            {{#composedSchemas}}
+            {{#oneOf}}
+            {{#isPrimitiveType}}
+            {{#isContainer}}
+            if ({{#lambda.camelcase_sanitize_param}}{{classname}}{{/lambda.camelcase_sanitize_param}}.{{name}} != null)
+            {
+                JsonSerializer.Serialize(writer, {{#lambda.camelcase_sanitize_param}}{{classname}}{{/lambda.camelcase_sanitize_param}}.{{name}}, jsonSerializerOptions);
+                return;
+            }
+
+            {{/isContainer}}
+            {{^isContainer}}
+            {{^vendorExtensions.x-duplicated-data-type}}
+            if ({{#lambda.camelcase_sanitize_param}}{{classname}}{{/lambda.camelcase_sanitize_param}}.{{name}} != null)
+            {
+                JsonSerializer.Serialize(writer, {{#lambda.camelcase_sanitize_param}}{{classname}}{{/lambda.camelcase_sanitize_param}}.{{name}}, jsonSerializerOptions);
+                return;
+            }
+
+            {{/vendorExtensions.x-duplicated-data-type}}
+            {{/isContainer}}
+            {{/isPrimitiveType}}
+            {{/oneOf}}
+            {{/composedSchemas}}
+            {{/model.discriminator}}
             writer.WriteStartObject();
+            {{^model.discriminator}}
+            {{#composedSchemas}}
+            {{#oneOf}}
+            {{^vendorExtensions.x-duplicated-data-type}}
+            {{#isModel}}
+            {{^isContainer}}
+            if ({{#lambda.camelcase_sanitize_param}}{{classname}}{{/lambda.camelcase_sanitize_param}}.{{name}} != null)
+            {
+                {{baseType}}JsonConverter {{#lambda.camelcase_sanitize_param}}{{baseType}}JsonConverter{{/lambda.camelcase_sanitize_param}} = ({{baseType}}JsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert({{#lambda.camelcase_sanitize_param}}{{classname}}{{/lambda.camelcase_sanitize_param}}.{{name}}.GetType()));
+                {{#lambda.camelcase_sanitize_param}}{{baseType}}JsonConverter{{/lambda.camelcase_sanitize_param}}.WriteProperties(writer, {{#lambda.camelcase_sanitize_param}}{{classname}}{{/lambda.camelcase_sanitize_param}}.{{name}}, jsonSerializerOptions);
+            }
+
+            {{/isContainer}}
+            {{/isModel}}
+            {{/vendorExtensions.x-duplicated-data-type}}
+            {{/oneOf}}
+            {{/composedSchemas}}
+            {{/model.discriminator}}
 
             {{#model.discriminator}}
             {{#model.hasDiscriminatorWithNonEmptyMapping}}
@@ -678,4 +755,4 @@
             {{/lambda.trimLineBreaks}}
             {{/lambda.trimTrailingWithNewLine}}
         }
-    }
\ No newline at end of file
+    }
diff --git a/modules/openapi-generator/src/test/resources/3_0/oneOf.yaml b/modules/openapi-generator/src/test/resources/3_0/oneOf.yaml
index 4aff70b18f28..63d9e0f65904 100644
--- a/modules/openapi-generator/src/test/resources/3_0/oneOf.yaml
+++ b/modules/openapi-generator/src/test/resources/3_0/oneOf.yaml
@@ -1,46 +1,68 @@
 openapi: 3.0.1
+
 info:
-   title: fruity
-   version: 0.0.1
+  title: fruity
+  version: 0.0.1
+
 paths:
-   /:
-      get:
-         responses:
-            '200':
-               description: desc
-               content:
-                  application/json:
-                     schema:
-                        $ref: '#/components/schemas/fruit'
+  /:
+    get:
+      responses:
+        '200':
+          description: desc
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/fruit'
+
 components:
-   schemas:
-      fruit:
-         title: fruit
-         properties:
-            color:
-               type: string
-         oneOf:
-            - $ref: '#/components/schemas/apple'
-            - $ref: '#/components/schemas/banana'
-            - $ref: '#/components/schemas/orange'
-         # additionalProperties:
-         #    type: string
-         # uncomment this when https://github.com/swagger-api/swagger-parser/issues/1252 is resolved
-      apple:
-         title: apple
-         type: object
-         properties:
-            kind:
-               type: string
-      banana:
-         title: banana
-         type: object
-         properties:
-            count:
-               type: number
-      orange:
-         title: orange
-         type: object
-         properties:
-            sweet:
-               type: boolean
+  schemas:
+    fruit:
+      title: fruit
+      properties:
+        color:
+          type: string
+      oneOf:
+        - $ref: '#/components/schemas/apple'
+        - $ref: '#/components/schemas/banana'
+        - $ref: '#/components/schemas/orange'
+
+    inlineOneOfModel:
+      title: inlineOneOfModel
+      type: object
+      properties:
+        value:
+          oneOf:
+            - type: string
+            - type: integer
+
+    union:
+      title: union
+      oneOf:
+        - type: string
+        - type: integer
+
+    apple:
+      title: apple
+      type: object
+      properties:
+        kind:
+          type: string
+
+    banana:
+      title: banana
+      type: object
+      properties:
+        count:
+          type: number
+
+    orange:
+      title: orange
+      type: object
+      properties:
+        sweet:
+          type: boolean
+
+# additionalProperties:
+#   type: string
+# uncomment this when https://github.com/swagger-api/swagger-parser/issues/1252 is resolved
\ No newline at end of file
diff --git a/samples/client/petstore/csharp/generichost/latest/AnnotatedEnum/src/Org.OpenAPITools/Model/OneOfNullableTest.cs b/samples/client/petstore/csharp/generichost/latest/AnnotatedEnum/src/Org.OpenAPITools/Model/OneOfNullableTest.cs
index 2d632afcb947..3910768cfdfe 100644
--- a/samples/client/petstore/csharp/generichost/latest/AnnotatedEnum/src/Org.OpenAPITools/Model/OneOfNullableTest.cs
+++ b/samples/client/petstore/csharp/generichost/latest/AnnotatedEnum/src/Org.OpenAPITools/Model/OneOfNullableTest.cs
@@ -179,6 +179,18 @@ public override OneOfNullableTest Read(ref Utf8JsonReader utf8JsonReader, Type t
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, OneOfNullableTest oneOfNullableTest, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (oneOfNullableTest.Int != null)
+            {
+                JsonSerializer.Serialize(writer, oneOfNullableTest.Int, jsonSerializerOptions);
+                return;
+            }
+
+            if (oneOfNullableTest.String != null)
+            {
+                JsonSerializer.Serialize(writer, oneOfNullableTest.String, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, oneOfNullableTest, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/latest/AnnotatedEnum/src/Org.OpenAPITools/Model/ParentWithPluralOneOfPropertyNumber.cs b/samples/client/petstore/csharp/generichost/latest/AnnotatedEnum/src/Org.OpenAPITools/Model/ParentWithPluralOneOfPropertyNumber.cs
index 42eb5c9cd94d..c582bc79731b 100644
--- a/samples/client/petstore/csharp/generichost/latest/AnnotatedEnum/src/Org.OpenAPITools/Model/ParentWithPluralOneOfPropertyNumber.cs
+++ b/samples/client/petstore/csharp/generichost/latest/AnnotatedEnum/src/Org.OpenAPITools/Model/ParentWithPluralOneOfPropertyNumber.cs
@@ -178,6 +178,18 @@ public override ParentWithPluralOneOfPropertyNumber Read(ref Utf8JsonReader utf8
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, ParentWithPluralOneOfPropertyNumber parentWithPluralOneOfPropertyNumber, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (parentWithPluralOneOfPropertyNumber.Number != null)
+            {
+                JsonSerializer.Serialize(writer, parentWithPluralOneOfPropertyNumber.Number, jsonSerializerOptions);
+                return;
+            }
+
+            if (parentWithPluralOneOfPropertyNumber.Number2 != null)
+            {
+                JsonSerializer.Serialize(writer, parentWithPluralOneOfPropertyNumber.Number2, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, parentWithPluralOneOfPropertyNumber, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/latest/OneOfList/src/Org.OpenAPITools.Test/Model/OneOfArrayRequestTests.cs b/samples/client/petstore/csharp/generichost/latest/OneOfList/src/Org.OpenAPITools.Test/Model/OneOfArrayRequestTests.cs
index 1dd0bbfa1260..c0dcd2245807 100644
--- a/samples/client/petstore/csharp/generichost/latest/OneOfList/src/Org.OpenAPITools.Test/Model/OneOfArrayRequestTests.cs
+++ b/samples/client/petstore/csharp/generichost/latest/OneOfList/src/Org.OpenAPITools.Test/Model/OneOfArrayRequestTests.cs
@@ -14,6 +14,7 @@
 using System.Linq;
 using System.IO;
 using System.Collections.Generic;
+using System.Text.Json;
 using Org.OpenAPITools.Model;
 using Org.OpenAPITools.Client;
 using System.Reflection;
@@ -52,5 +53,31 @@ public void OneOfArrayRequestInstanceTest()
             // TODO uncomment below to test "IsType" OneOfArrayRequest
             //Assert.IsType<OneOfArrayRequest>(instance);
         }
+
+        [Fact]
+        public void SerializeOneOfStringArray()
+        {
+            var options = new JsonSerializerOptions();
+            options.Converters.Add(new OneOfArrayRequestJsonConverter());
+            var request = new OneOfArrayRequest(new List<string> { "first", "second" });
+
+            string json = JsonSerializer.Serialize(request, options);
+
+            Assert.Equal("[\"first\",\"second\"]", json);
+        }
+
+        [Fact]
+        public void SerializeOneOfModelArray()
+        {
+            var options = new JsonSerializerOptions();
+            options.Converters.Add(new OneOfArrayRequestJsonConverter());
+            options.Converters.Add(new TestObjectJsonConverter());
+            var item = new TestObject(new Option<string?>("example"));
+            var request = new OneOfArrayRequest(new List<TestObject> { item });
+
+            string json = JsonSerializer.Serialize(request, options);
+
+            Assert.Equal("[{\"name\":\"example\"}]", json);
+        }
     }
 }
diff --git a/samples/client/petstore/csharp/generichost/latest/OneOfList/src/Org.OpenAPITools/Model/OneOfArrayRequest.cs b/samples/client/petstore/csharp/generichost/latest/OneOfList/src/Org.OpenAPITools/Model/OneOfArrayRequest.cs
index 8ce7469d7bca..e0c6959bd5cd 100644
--- a/samples/client/petstore/csharp/generichost/latest/OneOfList/src/Org.OpenAPITools/Model/OneOfArrayRequest.cs
+++ b/samples/client/petstore/csharp/generichost/latest/OneOfList/src/Org.OpenAPITools/Model/OneOfArrayRequest.cs
@@ -178,6 +178,18 @@ public override OneOfArrayRequest Read(ref Utf8JsonReader utf8JsonReader, Type t
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, OneOfArrayRequest oneOfArrayRequest, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (oneOfArrayRequest.List != null)
+            {
+                JsonSerializer.Serialize(writer, oneOfArrayRequest.List, jsonSerializerOptions);
+                return;
+            }
+
+            if (oneOfArrayRequest.List1 != null)
+            {
+                JsonSerializer.Serialize(writer, oneOfArrayRequest.List1, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, oneOfArrayRequest, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/latest/UseDateTimeOffset/src/Org.OpenAPITools/Model/Fruit.cs b/samples/client/petstore/csharp/generichost/latest/UseDateTimeOffset/src/Org.OpenAPITools/Model/Fruit.cs
index f6b30057b6ca..46a871ba0394 100644
--- a/samples/client/petstore/csharp/generichost/latest/UseDateTimeOffset/src/Org.OpenAPITools/Model/Fruit.cs
+++ b/samples/client/petstore/csharp/generichost/latest/UseDateTimeOffset/src/Org.OpenAPITools/Model/Fruit.cs
@@ -205,6 +205,17 @@ public override Fruit Read(ref Utf8JsonReader utf8JsonReader, Type typeToConvert
         public override void Write(Utf8JsonWriter writer, Fruit fruit, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruit.Apple != null)
+            {
+                AppleJsonConverter appleJsonConverter = (AppleJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Apple.GetType()));
+                appleJsonConverter.WriteProperties(writer, fruit.Apple, jsonSerializerOptions);
+            }
+
+            if (fruit.Banana != null)
+            {
+                BananaJsonConverter bananaJsonConverter = (BananaJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Banana.GetType()));
+                bananaJsonConverter.WriteProperties(writer, fruit.Banana, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruit, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/latest/UseDateTimeOffset/src/Org.OpenAPITools/Model/FruitReq.cs b/samples/client/petstore/csharp/generichost/latest/UseDateTimeOffset/src/Org.OpenAPITools/Model/FruitReq.cs
index 1b20a9969162..91f7e067f9b7 100644
--- a/samples/client/petstore/csharp/generichost/latest/UseDateTimeOffset/src/Org.OpenAPITools/Model/FruitReq.cs
+++ b/samples/client/petstore/csharp/generichost/latest/UseDateTimeOffset/src/Org.OpenAPITools/Model/FruitReq.cs
@@ -179,6 +179,17 @@ public override FruitReq Read(ref Utf8JsonReader utf8JsonReader, Type typeToConv
         public override void Write(Utf8JsonWriter writer, FruitReq fruitReq, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruitReq.AppleReq != null)
+            {
+                AppleReqJsonConverter appleReqJsonConverter = (AppleReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.AppleReq.GetType()));
+                appleReqJsonConverter.WriteProperties(writer, fruitReq.AppleReq, jsonSerializerOptions);
+            }
+
+            if (fruitReq.BananaReq != null)
+            {
+                BananaReqJsonConverter bananaReqJsonConverter = (BananaReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.BananaReq.GetType()));
+                bananaReqJsonConverter.WriteProperties(writer, fruitReq.BananaReq, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruitReq, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/latest/UseDateTimeOffset/src/Org.OpenAPITools/Model/MixedOneOfContent.cs b/samples/client/petstore/csharp/generichost/latest/UseDateTimeOffset/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
index 2712457d30f9..11396c56a846 100644
--- a/samples/client/petstore/csharp/generichost/latest/UseDateTimeOffset/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
+++ b/samples/client/petstore/csharp/generichost/latest/UseDateTimeOffset/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
@@ -244,7 +244,36 @@ public override MixedOneOfContent Read(ref Utf8JsonReader utf8JsonReader, Type t
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, MixedOneOfContent mixedOneOfContent, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (mixedOneOfContent.String != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Int != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Int, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Decimal != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Decimal, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
+            if (mixedOneOfContent.MixedSubId != null)
+            {
+                MixedSubIdJsonConverter mixedSubIdJsonConverter = (MixedSubIdJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(mixedOneOfContent.MixedSubId.GetType()));
+                mixedSubIdJsonConverter.WriteProperties(writer, mixedOneOfContent.MixedSubId, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, mixedOneOfContent, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/latest/UseDateTimeOffset/src/Org.OpenAPITools/Model/OneOfString.cs b/samples/client/petstore/csharp/generichost/latest/UseDateTimeOffset/src/Org.OpenAPITools/Model/OneOfString.cs
index f18374410642..d4887828f80f 100644
--- a/samples/client/petstore/csharp/generichost/latest/UseDateTimeOffset/src/Org.OpenAPITools/Model/OneOfString.cs
+++ b/samples/client/petstore/csharp/generichost/latest/UseDateTimeOffset/src/Org.OpenAPITools/Model/OneOfString.cs
@@ -140,6 +140,12 @@ public override OneOfString Read(ref Utf8JsonReader utf8JsonReader, Type typeToC
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, OneOfString oneOfString, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (oneOfString.String != null)
+            {
+                JsonSerializer.Serialize(writer, oneOfString.String, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, oneOfString, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/latest/UseDateTimeOffset/src/Org.OpenAPITools/Model/PolymorphicProperty.cs b/samples/client/petstore/csharp/generichost/latest/UseDateTimeOffset/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
index 9f2518b49d53..4e838c262f80 100644
--- a/samples/client/petstore/csharp/generichost/latest/UseDateTimeOffset/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
+++ b/samples/client/petstore/csharp/generichost/latest/UseDateTimeOffset/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
@@ -222,6 +222,30 @@ public override PolymorphicProperty Read(ref Utf8JsonReader utf8JsonReader, Type
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, PolymorphicProperty polymorphicProperty, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (polymorphicProperty.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.String != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.Object != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Object, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.List != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.List, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, polymorphicProperty, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/net10/FormModels/src/Org.OpenAPITools/Model/Fruit.cs b/samples/client/petstore/csharp/generichost/net10/FormModels/src/Org.OpenAPITools/Model/Fruit.cs
index ca703d27f96c..523e4981cf08 100644
--- a/samples/client/petstore/csharp/generichost/net10/FormModels/src/Org.OpenAPITools/Model/Fruit.cs
+++ b/samples/client/petstore/csharp/generichost/net10/FormModels/src/Org.OpenAPITools/Model/Fruit.cs
@@ -204,6 +204,17 @@ public override Fruit Read(ref Utf8JsonReader utf8JsonReader, Type typeToConvert
         public override void Write(Utf8JsonWriter writer, Fruit fruit, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruit.Apple != null)
+            {
+                AppleJsonConverter appleJsonConverter = (AppleJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Apple.GetType()));
+                appleJsonConverter.WriteProperties(writer, fruit.Apple, jsonSerializerOptions);
+            }
+
+            if (fruit.Banana != null)
+            {
+                BananaJsonConverter bananaJsonConverter = (BananaJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Banana.GetType()));
+                bananaJsonConverter.WriteProperties(writer, fruit.Banana, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruit, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net10/FormModels/src/Org.OpenAPITools/Model/FruitReq.cs b/samples/client/petstore/csharp/generichost/net10/FormModels/src/Org.OpenAPITools/Model/FruitReq.cs
index 440fbefb11ac..ac498f51caf9 100644
--- a/samples/client/petstore/csharp/generichost/net10/FormModels/src/Org.OpenAPITools/Model/FruitReq.cs
+++ b/samples/client/petstore/csharp/generichost/net10/FormModels/src/Org.OpenAPITools/Model/FruitReq.cs
@@ -178,6 +178,17 @@ public override FruitReq Read(ref Utf8JsonReader utf8JsonReader, Type typeToConv
         public override void Write(Utf8JsonWriter writer, FruitReq fruitReq, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruitReq.AppleReq != null)
+            {
+                AppleReqJsonConverter appleReqJsonConverter = (AppleReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.AppleReq.GetType()));
+                appleReqJsonConverter.WriteProperties(writer, fruitReq.AppleReq, jsonSerializerOptions);
+            }
+
+            if (fruitReq.BananaReq != null)
+            {
+                BananaReqJsonConverter bananaReqJsonConverter = (BananaReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.BananaReq.GetType()));
+                bananaReqJsonConverter.WriteProperties(writer, fruitReq.BananaReq, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruitReq, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net10/FormModels/src/Org.OpenAPITools/Model/MixedOneOfContent.cs b/samples/client/petstore/csharp/generichost/net10/FormModels/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
index 88d0a9a352de..270d653642cd 100644
--- a/samples/client/petstore/csharp/generichost/net10/FormModels/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
+++ b/samples/client/petstore/csharp/generichost/net10/FormModels/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
@@ -250,7 +250,36 @@ public override MixedOneOfContent Read(ref Utf8JsonReader utf8JsonReader, Type t
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, MixedOneOfContent mixedOneOfContent, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (mixedOneOfContent.String != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Int != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Int, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Decimal != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Decimal, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
+            if (mixedOneOfContent.MixedSubId != null)
+            {
+                MixedSubIdJsonConverter mixedSubIdJsonConverter = (MixedSubIdJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(mixedOneOfContent.MixedSubId.GetType()));
+                mixedSubIdJsonConverter.WriteProperties(writer, mixedOneOfContent.MixedSubId, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, mixedOneOfContent, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net10/FormModels/src/Org.OpenAPITools/Model/OneOfString.cs b/samples/client/petstore/csharp/generichost/net10/FormModels/src/Org.OpenAPITools/Model/OneOfString.cs
index af0ceaa278b0..b5b0a324b1eb 100644
--- a/samples/client/petstore/csharp/generichost/net10/FormModels/src/Org.OpenAPITools/Model/OneOfString.cs
+++ b/samples/client/petstore/csharp/generichost/net10/FormModels/src/Org.OpenAPITools/Model/OneOfString.cs
@@ -146,6 +146,12 @@ public override OneOfString Read(ref Utf8JsonReader utf8JsonReader, Type typeToC
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, OneOfString oneOfString, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (oneOfString.String != null)
+            {
+                JsonSerializer.Serialize(writer, oneOfString.String, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, oneOfString, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/net10/FormModels/src/Org.OpenAPITools/Model/PolymorphicProperty.cs b/samples/client/petstore/csharp/generichost/net10/FormModels/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
index befe6e02ec3a..c7ef5eda6387 100644
--- a/samples/client/petstore/csharp/generichost/net10/FormModels/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
+++ b/samples/client/petstore/csharp/generichost/net10/FormModels/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
@@ -228,6 +228,30 @@ public override PolymorphicProperty Read(ref Utf8JsonReader utf8JsonReader, Type
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, PolymorphicProperty polymorphicProperty, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (polymorphicProperty.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.String != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.Object != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Object, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.List != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.List, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, polymorphicProperty, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/net10/NullReferenceTypes/src/Org.OpenAPITools/Model/Fruit.cs b/samples/client/petstore/csharp/generichost/net10/NullReferenceTypes/src/Org.OpenAPITools/Model/Fruit.cs
index ec0062ba20d3..67cb3b13af6c 100644
--- a/samples/client/petstore/csharp/generichost/net10/NullReferenceTypes/src/Org.OpenAPITools/Model/Fruit.cs
+++ b/samples/client/petstore/csharp/generichost/net10/NullReferenceTypes/src/Org.OpenAPITools/Model/Fruit.cs
@@ -206,6 +206,17 @@ public override Fruit Read(ref Utf8JsonReader utf8JsonReader, Type typeToConvert
         public override void Write(Utf8JsonWriter writer, Fruit fruit, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruit.Apple != null)
+            {
+                AppleJsonConverter appleJsonConverter = (AppleJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Apple.GetType()));
+                appleJsonConverter.WriteProperties(writer, fruit.Apple, jsonSerializerOptions);
+            }
+
+            if (fruit.Banana != null)
+            {
+                BananaJsonConverter bananaJsonConverter = (BananaJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Banana.GetType()));
+                bananaJsonConverter.WriteProperties(writer, fruit.Banana, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruit, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net10/NullReferenceTypes/src/Org.OpenAPITools/Model/FruitReq.cs b/samples/client/petstore/csharp/generichost/net10/NullReferenceTypes/src/Org.OpenAPITools/Model/FruitReq.cs
index af1802aab1a9..d73d15fdc718 100644
--- a/samples/client/petstore/csharp/generichost/net10/NullReferenceTypes/src/Org.OpenAPITools/Model/FruitReq.cs
+++ b/samples/client/petstore/csharp/generichost/net10/NullReferenceTypes/src/Org.OpenAPITools/Model/FruitReq.cs
@@ -180,6 +180,17 @@ public override FruitReq Read(ref Utf8JsonReader utf8JsonReader, Type typeToConv
         public override void Write(Utf8JsonWriter writer, FruitReq fruitReq, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruitReq.AppleReq != null)
+            {
+                AppleReqJsonConverter appleReqJsonConverter = (AppleReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.AppleReq.GetType()));
+                appleReqJsonConverter.WriteProperties(writer, fruitReq.AppleReq, jsonSerializerOptions);
+            }
+
+            if (fruitReq.BananaReq != null)
+            {
+                BananaReqJsonConverter bananaReqJsonConverter = (BananaReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.BananaReq.GetType()));
+                bananaReqJsonConverter.WriteProperties(writer, fruitReq.BananaReq, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruitReq, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net10/NullReferenceTypes/src/Org.OpenAPITools/Model/MixedOneOfContent.cs b/samples/client/petstore/csharp/generichost/net10/NullReferenceTypes/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
index bac36e3cbe70..2b27c5610dad 100644
--- a/samples/client/petstore/csharp/generichost/net10/NullReferenceTypes/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
+++ b/samples/client/petstore/csharp/generichost/net10/NullReferenceTypes/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
@@ -252,7 +252,36 @@ public override MixedOneOfContent Read(ref Utf8JsonReader utf8JsonReader, Type t
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, MixedOneOfContent mixedOneOfContent, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (mixedOneOfContent.String != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Int != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Int, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Decimal != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Decimal, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
+            if (mixedOneOfContent.MixedSubId != null)
+            {
+                MixedSubIdJsonConverter mixedSubIdJsonConverter = (MixedSubIdJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(mixedOneOfContent.MixedSubId.GetType()));
+                mixedSubIdJsonConverter.WriteProperties(writer, mixedOneOfContent.MixedSubId, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, mixedOneOfContent, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net10/NullReferenceTypes/src/Org.OpenAPITools/Model/OneOfString.cs b/samples/client/petstore/csharp/generichost/net10/NullReferenceTypes/src/Org.OpenAPITools/Model/OneOfString.cs
index e03117058c32..50b6a7869b9f 100644
--- a/samples/client/petstore/csharp/generichost/net10/NullReferenceTypes/src/Org.OpenAPITools/Model/OneOfString.cs
+++ b/samples/client/petstore/csharp/generichost/net10/NullReferenceTypes/src/Org.OpenAPITools/Model/OneOfString.cs
@@ -148,6 +148,12 @@ public override OneOfString Read(ref Utf8JsonReader utf8JsonReader, Type typeToC
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, OneOfString oneOfString, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (oneOfString.String != null)
+            {
+                JsonSerializer.Serialize(writer, oneOfString.String, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, oneOfString, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/net10/NullReferenceTypes/src/Org.OpenAPITools/Model/PolymorphicProperty.cs b/samples/client/petstore/csharp/generichost/net10/NullReferenceTypes/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
index d33ed7654562..6aeb2e63b84d 100644
--- a/samples/client/petstore/csharp/generichost/net10/NullReferenceTypes/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
+++ b/samples/client/petstore/csharp/generichost/net10/NullReferenceTypes/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
@@ -230,6 +230,30 @@ public override PolymorphicProperty Read(ref Utf8JsonReader utf8JsonReader, Type
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, PolymorphicProperty polymorphicProperty, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (polymorphicProperty.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.String != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.Object != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Object, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.List != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.List, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, polymorphicProperty, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/net10/OneOf/src/Org.OpenAPITools/Model/Fruit.cs b/samples/client/petstore/csharp/generichost/net10/OneOf/src/Org.OpenAPITools/Model/Fruit.cs
index 1a4743015087..be03ed7e708e 100644
--- a/samples/client/petstore/csharp/generichost/net10/OneOf/src/Org.OpenAPITools/Model/Fruit.cs
+++ b/samples/client/petstore/csharp/generichost/net10/OneOf/src/Org.OpenAPITools/Model/Fruit.cs
@@ -237,6 +237,23 @@ public override Fruit Read(ref Utf8JsonReader utf8JsonReader, Type typeToConvert
         public override void Write(Utf8JsonWriter writer, Fruit fruit, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruit.Apple != null)
+            {
+                AppleJsonConverter appleJsonConverter = (AppleJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Apple.GetType()));
+                appleJsonConverter.WriteProperties(writer, fruit.Apple, jsonSerializerOptions);
+            }
+
+            if (fruit.Banana != null)
+            {
+                BananaJsonConverter bananaJsonConverter = (BananaJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Banana.GetType()));
+                bananaJsonConverter.WriteProperties(writer, fruit.Banana, jsonSerializerOptions);
+            }
+
+            if (fruit.Orange != null)
+            {
+                OrangeJsonConverter orangeJsonConverter = (OrangeJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Orange.GetType()));
+                orangeJsonConverter.WriteProperties(writer, fruit.Orange, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruit, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net10/Petstore/src/Org.OpenAPITools/Model/Fruit.cs b/samples/client/petstore/csharp/generichost/net10/Petstore/src/Org.OpenAPITools/Model/Fruit.cs
index ca703d27f96c..523e4981cf08 100644
--- a/samples/client/petstore/csharp/generichost/net10/Petstore/src/Org.OpenAPITools/Model/Fruit.cs
+++ b/samples/client/petstore/csharp/generichost/net10/Petstore/src/Org.OpenAPITools/Model/Fruit.cs
@@ -204,6 +204,17 @@ public override Fruit Read(ref Utf8JsonReader utf8JsonReader, Type typeToConvert
         public override void Write(Utf8JsonWriter writer, Fruit fruit, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruit.Apple != null)
+            {
+                AppleJsonConverter appleJsonConverter = (AppleJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Apple.GetType()));
+                appleJsonConverter.WriteProperties(writer, fruit.Apple, jsonSerializerOptions);
+            }
+
+            if (fruit.Banana != null)
+            {
+                BananaJsonConverter bananaJsonConverter = (BananaJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Banana.GetType()));
+                bananaJsonConverter.WriteProperties(writer, fruit.Banana, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruit, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net10/Petstore/src/Org.OpenAPITools/Model/FruitReq.cs b/samples/client/petstore/csharp/generichost/net10/Petstore/src/Org.OpenAPITools/Model/FruitReq.cs
index 440fbefb11ac..ac498f51caf9 100644
--- a/samples/client/petstore/csharp/generichost/net10/Petstore/src/Org.OpenAPITools/Model/FruitReq.cs
+++ b/samples/client/petstore/csharp/generichost/net10/Petstore/src/Org.OpenAPITools/Model/FruitReq.cs
@@ -178,6 +178,17 @@ public override FruitReq Read(ref Utf8JsonReader utf8JsonReader, Type typeToConv
         public override void Write(Utf8JsonWriter writer, FruitReq fruitReq, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruitReq.AppleReq != null)
+            {
+                AppleReqJsonConverter appleReqJsonConverter = (AppleReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.AppleReq.GetType()));
+                appleReqJsonConverter.WriteProperties(writer, fruitReq.AppleReq, jsonSerializerOptions);
+            }
+
+            if (fruitReq.BananaReq != null)
+            {
+                BananaReqJsonConverter bananaReqJsonConverter = (BananaReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.BananaReq.GetType()));
+                bananaReqJsonConverter.WriteProperties(writer, fruitReq.BananaReq, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruitReq, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net10/Petstore/src/Org.OpenAPITools/Model/MixedOneOfContent.cs b/samples/client/petstore/csharp/generichost/net10/Petstore/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
index 88d0a9a352de..270d653642cd 100644
--- a/samples/client/petstore/csharp/generichost/net10/Petstore/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
+++ b/samples/client/petstore/csharp/generichost/net10/Petstore/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
@@ -250,7 +250,36 @@ public override MixedOneOfContent Read(ref Utf8JsonReader utf8JsonReader, Type t
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, MixedOneOfContent mixedOneOfContent, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (mixedOneOfContent.String != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Int != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Int, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Decimal != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Decimal, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
+            if (mixedOneOfContent.MixedSubId != null)
+            {
+                MixedSubIdJsonConverter mixedSubIdJsonConverter = (MixedSubIdJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(mixedOneOfContent.MixedSubId.GetType()));
+                mixedSubIdJsonConverter.WriteProperties(writer, mixedOneOfContent.MixedSubId, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, mixedOneOfContent, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net10/Petstore/src/Org.OpenAPITools/Model/OneOfString.cs b/samples/client/petstore/csharp/generichost/net10/Petstore/src/Org.OpenAPITools/Model/OneOfString.cs
index af0ceaa278b0..b5b0a324b1eb 100644
--- a/samples/client/petstore/csharp/generichost/net10/Petstore/src/Org.OpenAPITools/Model/OneOfString.cs
+++ b/samples/client/petstore/csharp/generichost/net10/Petstore/src/Org.OpenAPITools/Model/OneOfString.cs
@@ -146,6 +146,12 @@ public override OneOfString Read(ref Utf8JsonReader utf8JsonReader, Type typeToC
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, OneOfString oneOfString, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (oneOfString.String != null)
+            {
+                JsonSerializer.Serialize(writer, oneOfString.String, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, oneOfString, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/net10/Petstore/src/Org.OpenAPITools/Model/PolymorphicProperty.cs b/samples/client/petstore/csharp/generichost/net10/Petstore/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
index befe6e02ec3a..c7ef5eda6387 100644
--- a/samples/client/petstore/csharp/generichost/net10/Petstore/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
+++ b/samples/client/petstore/csharp/generichost/net10/Petstore/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
@@ -228,6 +228,30 @@ public override PolymorphicProperty Read(ref Utf8JsonReader utf8JsonReader, Type
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, PolymorphicProperty polymorphicProperty, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (polymorphicProperty.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.String != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.Object != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Object, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.List != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.List, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, polymorphicProperty, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/net10/SourceGeneration/src/Org.OpenAPITools/Model/Fruit.cs b/samples/client/petstore/csharp/generichost/net10/SourceGeneration/src/Org.OpenAPITools/Model/Fruit.cs
index 9bad6c70417c..8e385da82a91 100644
--- a/samples/client/petstore/csharp/generichost/net10/SourceGeneration/src/Org.OpenAPITools/Model/Fruit.cs
+++ b/samples/client/petstore/csharp/generichost/net10/SourceGeneration/src/Org.OpenAPITools/Model/Fruit.cs
@@ -207,6 +207,17 @@ public override Fruit Read(ref Utf8JsonReader utf8JsonReader, Type typeToConvert
         public override void Write(Utf8JsonWriter writer, Fruit fruit, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruit.Apple != null)
+            {
+                AppleJsonConverter appleJsonConverter = (AppleJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Apple.GetType()));
+                appleJsonConverter.WriteProperties(writer, fruit.Apple, jsonSerializerOptions);
+            }
+
+            if (fruit.Banana != null)
+            {
+                BananaJsonConverter bananaJsonConverter = (BananaJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Banana.GetType()));
+                bananaJsonConverter.WriteProperties(writer, fruit.Banana, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruit, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net10/SourceGeneration/src/Org.OpenAPITools/Model/FruitReq.cs b/samples/client/petstore/csharp/generichost/net10/SourceGeneration/src/Org.OpenAPITools/Model/FruitReq.cs
index ed5e1e35c028..361da9371288 100644
--- a/samples/client/petstore/csharp/generichost/net10/SourceGeneration/src/Org.OpenAPITools/Model/FruitReq.cs
+++ b/samples/client/petstore/csharp/generichost/net10/SourceGeneration/src/Org.OpenAPITools/Model/FruitReq.cs
@@ -181,6 +181,17 @@ public override FruitReq Read(ref Utf8JsonReader utf8JsonReader, Type typeToConv
         public override void Write(Utf8JsonWriter writer, FruitReq fruitReq, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruitReq.AppleReq != null)
+            {
+                AppleReqJsonConverter appleReqJsonConverter = (AppleReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.AppleReq.GetType()));
+                appleReqJsonConverter.WriteProperties(writer, fruitReq.AppleReq, jsonSerializerOptions);
+            }
+
+            if (fruitReq.BananaReq != null)
+            {
+                BananaReqJsonConverter bananaReqJsonConverter = (BananaReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.BananaReq.GetType()));
+                bananaReqJsonConverter.WriteProperties(writer, fruitReq.BananaReq, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruitReq, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net10/SourceGeneration/src/Org.OpenAPITools/Model/MixedOneOfContent.cs b/samples/client/petstore/csharp/generichost/net10/SourceGeneration/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
index ca6ca27187dd..c96886067b6b 100644
--- a/samples/client/petstore/csharp/generichost/net10/SourceGeneration/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
+++ b/samples/client/petstore/csharp/generichost/net10/SourceGeneration/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
@@ -253,7 +253,36 @@ public override MixedOneOfContent Read(ref Utf8JsonReader utf8JsonReader, Type t
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, MixedOneOfContent mixedOneOfContent, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (mixedOneOfContent.String != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Int != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Int, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Decimal != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Decimal, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
+            if (mixedOneOfContent.MixedSubId != null)
+            {
+                MixedSubIdJsonConverter mixedSubIdJsonConverter = (MixedSubIdJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(mixedOneOfContent.MixedSubId.GetType()));
+                mixedSubIdJsonConverter.WriteProperties(writer, mixedOneOfContent.MixedSubId, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, mixedOneOfContent, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net10/SourceGeneration/src/Org.OpenAPITools/Model/OneOfString.cs b/samples/client/petstore/csharp/generichost/net10/SourceGeneration/src/Org.OpenAPITools/Model/OneOfString.cs
index 4a46f52ead3a..df1341c55fed 100644
--- a/samples/client/petstore/csharp/generichost/net10/SourceGeneration/src/Org.OpenAPITools/Model/OneOfString.cs
+++ b/samples/client/petstore/csharp/generichost/net10/SourceGeneration/src/Org.OpenAPITools/Model/OneOfString.cs
@@ -149,6 +149,12 @@ public override OneOfString Read(ref Utf8JsonReader utf8JsonReader, Type typeToC
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, OneOfString oneOfString, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (oneOfString.String != null)
+            {
+                JsonSerializer.Serialize(writer, oneOfString.String, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, oneOfString, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/net10/SourceGeneration/src/Org.OpenAPITools/Model/PolymorphicProperty.cs b/samples/client/petstore/csharp/generichost/net10/SourceGeneration/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
index d3e959b95a67..114391721fd3 100644
--- a/samples/client/petstore/csharp/generichost/net10/SourceGeneration/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
+++ b/samples/client/petstore/csharp/generichost/net10/SourceGeneration/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
@@ -231,6 +231,30 @@ public override PolymorphicProperty Read(ref Utf8JsonReader utf8JsonReader, Type
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, PolymorphicProperty polymorphicProperty, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (polymorphicProperty.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.String != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.Object != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Object, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.List != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.List, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, polymorphicProperty, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/net4.7/FormModels/src/Org.OpenAPITools/Model/Fruit.cs b/samples/client/petstore/csharp/generichost/net4.7/FormModels/src/Org.OpenAPITools/Model/Fruit.cs
index ba5d85932b34..453be949b65f 100644
--- a/samples/client/petstore/csharp/generichost/net4.7/FormModels/src/Org.OpenAPITools/Model/Fruit.cs
+++ b/samples/client/petstore/csharp/generichost/net4.7/FormModels/src/Org.OpenAPITools/Model/Fruit.cs
@@ -204,6 +204,17 @@ public override Fruit Read(ref Utf8JsonReader utf8JsonReader, Type typeToConvert
         public override void Write(Utf8JsonWriter writer, Fruit fruit, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruit.Apple != null)
+            {
+                AppleJsonConverter appleJsonConverter = (AppleJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Apple.GetType()));
+                appleJsonConverter.WriteProperties(writer, fruit.Apple, jsonSerializerOptions);
+            }
+
+            if (fruit.Banana != null)
+            {
+                BananaJsonConverter bananaJsonConverter = (BananaJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Banana.GetType()));
+                bananaJsonConverter.WriteProperties(writer, fruit.Banana, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruit, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net4.7/FormModels/src/Org.OpenAPITools/Model/FruitReq.cs b/samples/client/petstore/csharp/generichost/net4.7/FormModels/src/Org.OpenAPITools/Model/FruitReq.cs
index 440fbefb11ac..ac498f51caf9 100644
--- a/samples/client/petstore/csharp/generichost/net4.7/FormModels/src/Org.OpenAPITools/Model/FruitReq.cs
+++ b/samples/client/petstore/csharp/generichost/net4.7/FormModels/src/Org.OpenAPITools/Model/FruitReq.cs
@@ -178,6 +178,17 @@ public override FruitReq Read(ref Utf8JsonReader utf8JsonReader, Type typeToConv
         public override void Write(Utf8JsonWriter writer, FruitReq fruitReq, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruitReq.AppleReq != null)
+            {
+                AppleReqJsonConverter appleReqJsonConverter = (AppleReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.AppleReq.GetType()));
+                appleReqJsonConverter.WriteProperties(writer, fruitReq.AppleReq, jsonSerializerOptions);
+            }
+
+            if (fruitReq.BananaReq != null)
+            {
+                BananaReqJsonConverter bananaReqJsonConverter = (BananaReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.BananaReq.GetType()));
+                bananaReqJsonConverter.WriteProperties(writer, fruitReq.BananaReq, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruitReq, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net4.7/FormModels/src/Org.OpenAPITools/Model/MixedOneOfContent.cs b/samples/client/petstore/csharp/generichost/net4.7/FormModels/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
index 88d0a9a352de..270d653642cd 100644
--- a/samples/client/petstore/csharp/generichost/net4.7/FormModels/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
+++ b/samples/client/petstore/csharp/generichost/net4.7/FormModels/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
@@ -250,7 +250,36 @@ public override MixedOneOfContent Read(ref Utf8JsonReader utf8JsonReader, Type t
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, MixedOneOfContent mixedOneOfContent, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (mixedOneOfContent.String != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Int != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Int, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Decimal != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Decimal, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
+            if (mixedOneOfContent.MixedSubId != null)
+            {
+                MixedSubIdJsonConverter mixedSubIdJsonConverter = (MixedSubIdJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(mixedOneOfContent.MixedSubId.GetType()));
+                mixedSubIdJsonConverter.WriteProperties(writer, mixedOneOfContent.MixedSubId, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, mixedOneOfContent, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net4.7/FormModels/src/Org.OpenAPITools/Model/OneOfString.cs b/samples/client/petstore/csharp/generichost/net4.7/FormModels/src/Org.OpenAPITools/Model/OneOfString.cs
index af0ceaa278b0..b5b0a324b1eb 100644
--- a/samples/client/petstore/csharp/generichost/net4.7/FormModels/src/Org.OpenAPITools/Model/OneOfString.cs
+++ b/samples/client/petstore/csharp/generichost/net4.7/FormModels/src/Org.OpenAPITools/Model/OneOfString.cs
@@ -146,6 +146,12 @@ public override OneOfString Read(ref Utf8JsonReader utf8JsonReader, Type typeToC
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, OneOfString oneOfString, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (oneOfString.String != null)
+            {
+                JsonSerializer.Serialize(writer, oneOfString.String, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, oneOfString, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/net4.7/FormModels/src/Org.OpenAPITools/Model/PolymorphicProperty.cs b/samples/client/petstore/csharp/generichost/net4.7/FormModels/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
index befe6e02ec3a..c7ef5eda6387 100644
--- a/samples/client/petstore/csharp/generichost/net4.7/FormModels/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
+++ b/samples/client/petstore/csharp/generichost/net4.7/FormModels/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
@@ -228,6 +228,30 @@ public override PolymorphicProperty Read(ref Utf8JsonReader utf8JsonReader, Type
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, PolymorphicProperty polymorphicProperty, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (polymorphicProperty.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.String != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.Object != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Object, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.List != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.List, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, polymorphicProperty, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/net4.7/OneOf/src/Org.OpenAPITools/Model/Fruit.cs b/samples/client/petstore/csharp/generichost/net4.7/OneOf/src/Org.OpenAPITools/Model/Fruit.cs
index e2e2f33c524d..617047885a4a 100644
--- a/samples/client/petstore/csharp/generichost/net4.7/OneOf/src/Org.OpenAPITools/Model/Fruit.cs
+++ b/samples/client/petstore/csharp/generichost/net4.7/OneOf/src/Org.OpenAPITools/Model/Fruit.cs
@@ -235,6 +235,23 @@ public override Fruit Read(ref Utf8JsonReader utf8JsonReader, Type typeToConvert
         public override void Write(Utf8JsonWriter writer, Fruit fruit, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruit.Apple != null)
+            {
+                AppleJsonConverter appleJsonConverter = (AppleJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Apple.GetType()));
+                appleJsonConverter.WriteProperties(writer, fruit.Apple, jsonSerializerOptions);
+            }
+
+            if (fruit.Banana != null)
+            {
+                BananaJsonConverter bananaJsonConverter = (BananaJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Banana.GetType()));
+                bananaJsonConverter.WriteProperties(writer, fruit.Banana, jsonSerializerOptions);
+            }
+
+            if (fruit.Orange != null)
+            {
+                OrangeJsonConverter orangeJsonConverter = (OrangeJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Orange.GetType()));
+                orangeJsonConverter.WriteProperties(writer, fruit.Orange, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruit, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net4.7/Petstore/src/Org.OpenAPITools/Model/Fruit.cs b/samples/client/petstore/csharp/generichost/net4.7/Petstore/src/Org.OpenAPITools/Model/Fruit.cs
index ba5d85932b34..453be949b65f 100644
--- a/samples/client/petstore/csharp/generichost/net4.7/Petstore/src/Org.OpenAPITools/Model/Fruit.cs
+++ b/samples/client/petstore/csharp/generichost/net4.7/Petstore/src/Org.OpenAPITools/Model/Fruit.cs
@@ -204,6 +204,17 @@ public override Fruit Read(ref Utf8JsonReader utf8JsonReader, Type typeToConvert
         public override void Write(Utf8JsonWriter writer, Fruit fruit, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruit.Apple != null)
+            {
+                AppleJsonConverter appleJsonConverter = (AppleJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Apple.GetType()));
+                appleJsonConverter.WriteProperties(writer, fruit.Apple, jsonSerializerOptions);
+            }
+
+            if (fruit.Banana != null)
+            {
+                BananaJsonConverter bananaJsonConverter = (BananaJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Banana.GetType()));
+                bananaJsonConverter.WriteProperties(writer, fruit.Banana, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruit, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net4.7/Petstore/src/Org.OpenAPITools/Model/FruitReq.cs b/samples/client/petstore/csharp/generichost/net4.7/Petstore/src/Org.OpenAPITools/Model/FruitReq.cs
index 440fbefb11ac..ac498f51caf9 100644
--- a/samples/client/petstore/csharp/generichost/net4.7/Petstore/src/Org.OpenAPITools/Model/FruitReq.cs
+++ b/samples/client/petstore/csharp/generichost/net4.7/Petstore/src/Org.OpenAPITools/Model/FruitReq.cs
@@ -178,6 +178,17 @@ public override FruitReq Read(ref Utf8JsonReader utf8JsonReader, Type typeToConv
         public override void Write(Utf8JsonWriter writer, FruitReq fruitReq, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruitReq.AppleReq != null)
+            {
+                AppleReqJsonConverter appleReqJsonConverter = (AppleReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.AppleReq.GetType()));
+                appleReqJsonConverter.WriteProperties(writer, fruitReq.AppleReq, jsonSerializerOptions);
+            }
+
+            if (fruitReq.BananaReq != null)
+            {
+                BananaReqJsonConverter bananaReqJsonConverter = (BananaReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.BananaReq.GetType()));
+                bananaReqJsonConverter.WriteProperties(writer, fruitReq.BananaReq, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruitReq, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net4.7/Petstore/src/Org.OpenAPITools/Model/MixedOneOfContent.cs b/samples/client/petstore/csharp/generichost/net4.7/Petstore/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
index 88d0a9a352de..270d653642cd 100644
--- a/samples/client/petstore/csharp/generichost/net4.7/Petstore/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
+++ b/samples/client/petstore/csharp/generichost/net4.7/Petstore/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
@@ -250,7 +250,36 @@ public override MixedOneOfContent Read(ref Utf8JsonReader utf8JsonReader, Type t
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, MixedOneOfContent mixedOneOfContent, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (mixedOneOfContent.String != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Int != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Int, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Decimal != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Decimal, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
+            if (mixedOneOfContent.MixedSubId != null)
+            {
+                MixedSubIdJsonConverter mixedSubIdJsonConverter = (MixedSubIdJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(mixedOneOfContent.MixedSubId.GetType()));
+                mixedSubIdJsonConverter.WriteProperties(writer, mixedOneOfContent.MixedSubId, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, mixedOneOfContent, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net4.7/Petstore/src/Org.OpenAPITools/Model/OneOfString.cs b/samples/client/petstore/csharp/generichost/net4.7/Petstore/src/Org.OpenAPITools/Model/OneOfString.cs
index af0ceaa278b0..b5b0a324b1eb 100644
--- a/samples/client/petstore/csharp/generichost/net4.7/Petstore/src/Org.OpenAPITools/Model/OneOfString.cs
+++ b/samples/client/petstore/csharp/generichost/net4.7/Petstore/src/Org.OpenAPITools/Model/OneOfString.cs
@@ -146,6 +146,12 @@ public override OneOfString Read(ref Utf8JsonReader utf8JsonReader, Type typeToC
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, OneOfString oneOfString, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (oneOfString.String != null)
+            {
+                JsonSerializer.Serialize(writer, oneOfString.String, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, oneOfString, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/net4.7/Petstore/src/Org.OpenAPITools/Model/PolymorphicProperty.cs b/samples/client/petstore/csharp/generichost/net4.7/Petstore/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
index befe6e02ec3a..c7ef5eda6387 100644
--- a/samples/client/petstore/csharp/generichost/net4.7/Petstore/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
+++ b/samples/client/petstore/csharp/generichost/net4.7/Petstore/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
@@ -228,6 +228,30 @@ public override PolymorphicProperty Read(ref Utf8JsonReader utf8JsonReader, Type
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, PolymorphicProperty polymorphicProperty, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (polymorphicProperty.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.String != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.Object != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Object, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.List != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.List, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, polymorphicProperty, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/net4.8/FormModels/src/Org.OpenAPITools/Model/Fruit.cs b/samples/client/petstore/csharp/generichost/net4.8/FormModels/src/Org.OpenAPITools/Model/Fruit.cs
index ba5d85932b34..453be949b65f 100644
--- a/samples/client/petstore/csharp/generichost/net4.8/FormModels/src/Org.OpenAPITools/Model/Fruit.cs
+++ b/samples/client/petstore/csharp/generichost/net4.8/FormModels/src/Org.OpenAPITools/Model/Fruit.cs
@@ -204,6 +204,17 @@ public override Fruit Read(ref Utf8JsonReader utf8JsonReader, Type typeToConvert
         public override void Write(Utf8JsonWriter writer, Fruit fruit, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruit.Apple != null)
+            {
+                AppleJsonConverter appleJsonConverter = (AppleJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Apple.GetType()));
+                appleJsonConverter.WriteProperties(writer, fruit.Apple, jsonSerializerOptions);
+            }
+
+            if (fruit.Banana != null)
+            {
+                BananaJsonConverter bananaJsonConverter = (BananaJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Banana.GetType()));
+                bananaJsonConverter.WriteProperties(writer, fruit.Banana, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruit, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net4.8/FormModels/src/Org.OpenAPITools/Model/FruitReq.cs b/samples/client/petstore/csharp/generichost/net4.8/FormModels/src/Org.OpenAPITools/Model/FruitReq.cs
index 440fbefb11ac..ac498f51caf9 100644
--- a/samples/client/petstore/csharp/generichost/net4.8/FormModels/src/Org.OpenAPITools/Model/FruitReq.cs
+++ b/samples/client/petstore/csharp/generichost/net4.8/FormModels/src/Org.OpenAPITools/Model/FruitReq.cs
@@ -178,6 +178,17 @@ public override FruitReq Read(ref Utf8JsonReader utf8JsonReader, Type typeToConv
         public override void Write(Utf8JsonWriter writer, FruitReq fruitReq, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruitReq.AppleReq != null)
+            {
+                AppleReqJsonConverter appleReqJsonConverter = (AppleReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.AppleReq.GetType()));
+                appleReqJsonConverter.WriteProperties(writer, fruitReq.AppleReq, jsonSerializerOptions);
+            }
+
+            if (fruitReq.BananaReq != null)
+            {
+                BananaReqJsonConverter bananaReqJsonConverter = (BananaReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.BananaReq.GetType()));
+                bananaReqJsonConverter.WriteProperties(writer, fruitReq.BananaReq, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruitReq, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net4.8/FormModels/src/Org.OpenAPITools/Model/MixedOneOfContent.cs b/samples/client/petstore/csharp/generichost/net4.8/FormModels/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
index 88d0a9a352de..270d653642cd 100644
--- a/samples/client/petstore/csharp/generichost/net4.8/FormModels/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
+++ b/samples/client/petstore/csharp/generichost/net4.8/FormModels/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
@@ -250,7 +250,36 @@ public override MixedOneOfContent Read(ref Utf8JsonReader utf8JsonReader, Type t
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, MixedOneOfContent mixedOneOfContent, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (mixedOneOfContent.String != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Int != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Int, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Decimal != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Decimal, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
+            if (mixedOneOfContent.MixedSubId != null)
+            {
+                MixedSubIdJsonConverter mixedSubIdJsonConverter = (MixedSubIdJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(mixedOneOfContent.MixedSubId.GetType()));
+                mixedSubIdJsonConverter.WriteProperties(writer, mixedOneOfContent.MixedSubId, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, mixedOneOfContent, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net4.8/FormModels/src/Org.OpenAPITools/Model/OneOfString.cs b/samples/client/petstore/csharp/generichost/net4.8/FormModels/src/Org.OpenAPITools/Model/OneOfString.cs
index af0ceaa278b0..b5b0a324b1eb 100644
--- a/samples/client/petstore/csharp/generichost/net4.8/FormModels/src/Org.OpenAPITools/Model/OneOfString.cs
+++ b/samples/client/petstore/csharp/generichost/net4.8/FormModels/src/Org.OpenAPITools/Model/OneOfString.cs
@@ -146,6 +146,12 @@ public override OneOfString Read(ref Utf8JsonReader utf8JsonReader, Type typeToC
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, OneOfString oneOfString, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (oneOfString.String != null)
+            {
+                JsonSerializer.Serialize(writer, oneOfString.String, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, oneOfString, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/net4.8/FormModels/src/Org.OpenAPITools/Model/PolymorphicProperty.cs b/samples/client/petstore/csharp/generichost/net4.8/FormModels/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
index befe6e02ec3a..c7ef5eda6387 100644
--- a/samples/client/petstore/csharp/generichost/net4.8/FormModels/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
+++ b/samples/client/petstore/csharp/generichost/net4.8/FormModels/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
@@ -228,6 +228,30 @@ public override PolymorphicProperty Read(ref Utf8JsonReader utf8JsonReader, Type
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, PolymorphicProperty polymorphicProperty, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (polymorphicProperty.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.String != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.Object != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Object, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.List != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.List, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, polymorphicProperty, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/net4.8/OneOf/src/Org.OpenAPITools/Model/Fruit.cs b/samples/client/petstore/csharp/generichost/net4.8/OneOf/src/Org.OpenAPITools/Model/Fruit.cs
index e2e2f33c524d..617047885a4a 100644
--- a/samples/client/petstore/csharp/generichost/net4.8/OneOf/src/Org.OpenAPITools/Model/Fruit.cs
+++ b/samples/client/petstore/csharp/generichost/net4.8/OneOf/src/Org.OpenAPITools/Model/Fruit.cs
@@ -235,6 +235,23 @@ public override Fruit Read(ref Utf8JsonReader utf8JsonReader, Type typeToConvert
         public override void Write(Utf8JsonWriter writer, Fruit fruit, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruit.Apple != null)
+            {
+                AppleJsonConverter appleJsonConverter = (AppleJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Apple.GetType()));
+                appleJsonConverter.WriteProperties(writer, fruit.Apple, jsonSerializerOptions);
+            }
+
+            if (fruit.Banana != null)
+            {
+                BananaJsonConverter bananaJsonConverter = (BananaJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Banana.GetType()));
+                bananaJsonConverter.WriteProperties(writer, fruit.Banana, jsonSerializerOptions);
+            }
+
+            if (fruit.Orange != null)
+            {
+                OrangeJsonConverter orangeJsonConverter = (OrangeJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Orange.GetType()));
+                orangeJsonConverter.WriteProperties(writer, fruit.Orange, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruit, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net4.8/Petstore/src/Org.OpenAPITools/Model/Fruit.cs b/samples/client/petstore/csharp/generichost/net4.8/Petstore/src/Org.OpenAPITools/Model/Fruit.cs
index ba5d85932b34..453be949b65f 100644
--- a/samples/client/petstore/csharp/generichost/net4.8/Petstore/src/Org.OpenAPITools/Model/Fruit.cs
+++ b/samples/client/petstore/csharp/generichost/net4.8/Petstore/src/Org.OpenAPITools/Model/Fruit.cs
@@ -204,6 +204,17 @@ public override Fruit Read(ref Utf8JsonReader utf8JsonReader, Type typeToConvert
         public override void Write(Utf8JsonWriter writer, Fruit fruit, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruit.Apple != null)
+            {
+                AppleJsonConverter appleJsonConverter = (AppleJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Apple.GetType()));
+                appleJsonConverter.WriteProperties(writer, fruit.Apple, jsonSerializerOptions);
+            }
+
+            if (fruit.Banana != null)
+            {
+                BananaJsonConverter bananaJsonConverter = (BananaJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Banana.GetType()));
+                bananaJsonConverter.WriteProperties(writer, fruit.Banana, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruit, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net4.8/Petstore/src/Org.OpenAPITools/Model/FruitReq.cs b/samples/client/petstore/csharp/generichost/net4.8/Petstore/src/Org.OpenAPITools/Model/FruitReq.cs
index 440fbefb11ac..ac498f51caf9 100644
--- a/samples/client/petstore/csharp/generichost/net4.8/Petstore/src/Org.OpenAPITools/Model/FruitReq.cs
+++ b/samples/client/petstore/csharp/generichost/net4.8/Petstore/src/Org.OpenAPITools/Model/FruitReq.cs
@@ -178,6 +178,17 @@ public override FruitReq Read(ref Utf8JsonReader utf8JsonReader, Type typeToConv
         public override void Write(Utf8JsonWriter writer, FruitReq fruitReq, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruitReq.AppleReq != null)
+            {
+                AppleReqJsonConverter appleReqJsonConverter = (AppleReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.AppleReq.GetType()));
+                appleReqJsonConverter.WriteProperties(writer, fruitReq.AppleReq, jsonSerializerOptions);
+            }
+
+            if (fruitReq.BananaReq != null)
+            {
+                BananaReqJsonConverter bananaReqJsonConverter = (BananaReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.BananaReq.GetType()));
+                bananaReqJsonConverter.WriteProperties(writer, fruitReq.BananaReq, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruitReq, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net4.8/Petstore/src/Org.OpenAPITools/Model/MixedOneOfContent.cs b/samples/client/petstore/csharp/generichost/net4.8/Petstore/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
index 88d0a9a352de..270d653642cd 100644
--- a/samples/client/petstore/csharp/generichost/net4.8/Petstore/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
+++ b/samples/client/petstore/csharp/generichost/net4.8/Petstore/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
@@ -250,7 +250,36 @@ public override MixedOneOfContent Read(ref Utf8JsonReader utf8JsonReader, Type t
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, MixedOneOfContent mixedOneOfContent, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (mixedOneOfContent.String != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Int != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Int, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Decimal != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Decimal, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
+            if (mixedOneOfContent.MixedSubId != null)
+            {
+                MixedSubIdJsonConverter mixedSubIdJsonConverter = (MixedSubIdJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(mixedOneOfContent.MixedSubId.GetType()));
+                mixedSubIdJsonConverter.WriteProperties(writer, mixedOneOfContent.MixedSubId, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, mixedOneOfContent, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net4.8/Petstore/src/Org.OpenAPITools/Model/OneOfString.cs b/samples/client/petstore/csharp/generichost/net4.8/Petstore/src/Org.OpenAPITools/Model/OneOfString.cs
index af0ceaa278b0..b5b0a324b1eb 100644
--- a/samples/client/petstore/csharp/generichost/net4.8/Petstore/src/Org.OpenAPITools/Model/OneOfString.cs
+++ b/samples/client/petstore/csharp/generichost/net4.8/Petstore/src/Org.OpenAPITools/Model/OneOfString.cs
@@ -146,6 +146,12 @@ public override OneOfString Read(ref Utf8JsonReader utf8JsonReader, Type typeToC
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, OneOfString oneOfString, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (oneOfString.String != null)
+            {
+                JsonSerializer.Serialize(writer, oneOfString.String, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, oneOfString, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/net4.8/Petstore/src/Org.OpenAPITools/Model/PolymorphicProperty.cs b/samples/client/petstore/csharp/generichost/net4.8/Petstore/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
index befe6e02ec3a..c7ef5eda6387 100644
--- a/samples/client/petstore/csharp/generichost/net4.8/Petstore/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
+++ b/samples/client/petstore/csharp/generichost/net4.8/Petstore/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
@@ -228,6 +228,30 @@ public override PolymorphicProperty Read(ref Utf8JsonReader utf8JsonReader, Type
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, PolymorphicProperty polymorphicProperty, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (polymorphicProperty.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.String != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.Object != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Object, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.List != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.List, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, polymorphicProperty, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/Fruit.cs b/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/Fruit.cs
index ca703d27f96c..c9638e5b9882 100644
--- a/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/Fruit.cs
+++ b/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/Fruit.cs
@@ -129,9 +129,6 @@ public override Fruit Read(ref Utf8JsonReader utf8JsonReader, Type typeToConvert
         {
             int currentDepth = utf8JsonReader.CurrentDepth;
 
-            if (utf8JsonReader.TokenType != JsonTokenType.StartObject && utf8JsonReader.TokenType != JsonTokenType.StartArray)
-                throw new JsonException();
-
             JsonTokenType startingTokenType = utf8JsonReader.TokenType;
 
             Option<string> color = default;
@@ -139,22 +136,33 @@ public override Fruit Read(ref Utf8JsonReader utf8JsonReader, Type typeToConvert
             Apple apple = default;
             Banana banana = default;
 
-            Utf8JsonReader utf8JsonReaderOneOf = utf8JsonReader;
-            while (utf8JsonReaderOneOf.Read())
+            if (startingTokenType != JsonTokenType.StartObject && startingTokenType != JsonTokenType.StartArray)
             {
-                if (startingTokenType == JsonTokenType.StartObject && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndObject && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
-                    break;
-
-                if (startingTokenType == JsonTokenType.StartArray && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndArray && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
-                    break;
+                Utf8JsonReader utf8JsonReaderApple = utf8JsonReader;
+                ClientUtils.TryDeserialize<Apple>(ref utf8JsonReaderApple, jsonSerializerOptions, out apple);
 
-                if (utf8JsonReaderOneOf.TokenType == JsonTokenType.PropertyName && currentDepth == utf8JsonReaderOneOf.CurrentDepth - 1)
+                Utf8JsonReader utf8JsonReaderBanana = utf8JsonReader;
+                ClientUtils.TryDeserialize<Banana>(ref utf8JsonReaderBanana, jsonSerializerOptions, out banana);
+            }
+            else
+            {
+                Utf8JsonReader utf8JsonReaderOneOf = utf8JsonReader;
+                while (utf8JsonReaderOneOf.Read())
                 {
-                    Utf8JsonReader utf8JsonReaderApple = utf8JsonReader;
-                    ClientUtils.TryDeserialize<Apple>(ref utf8JsonReaderApple, jsonSerializerOptions, out apple);
+                    if (startingTokenType == JsonTokenType.StartObject && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndObject && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
+                        break;
 
-                    Utf8JsonReader utf8JsonReaderBanana = utf8JsonReader;
-                    ClientUtils.TryDeserialize<Banana>(ref utf8JsonReaderBanana, jsonSerializerOptions, out banana);
+                    if (startingTokenType == JsonTokenType.StartArray && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndArray && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
+                        break;
+
+                    if (utf8JsonReaderOneOf.TokenType == JsonTokenType.PropertyName && currentDepth == utf8JsonReaderOneOf.CurrentDepth - 1)
+                    {
+                        Utf8JsonReader utf8JsonReaderApple = utf8JsonReader;
+                        ClientUtils.TryDeserialize<Apple>(ref utf8JsonReaderApple, jsonSerializerOptions, out apple);
+
+                        Utf8JsonReader utf8JsonReaderBanana = utf8JsonReader;
+                        ClientUtils.TryDeserialize<Banana>(ref utf8JsonReaderBanana, jsonSerializerOptions, out banana);
+                    }
                 }
             }
 
@@ -204,6 +212,17 @@ public override Fruit Read(ref Utf8JsonReader utf8JsonReader, Type typeToConvert
         public override void Write(Utf8JsonWriter writer, Fruit fruit, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruit.Apple != null)
+            {
+                AppleJsonConverter appleJsonConverter = (AppleJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Apple.GetType()));
+                appleJsonConverter.WriteProperties(writer, fruit.Apple, jsonSerializerOptions);
+            }
+
+            if (fruit.Banana != null)
+            {
+                BananaJsonConverter bananaJsonConverter = (BananaJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Banana.GetType()));
+                bananaJsonConverter.WriteProperties(writer, fruit.Banana, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruit, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/FruitReq.cs b/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/FruitReq.cs
index 440fbefb11ac..2bb8e810357b 100644
--- a/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/FruitReq.cs
+++ b/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/FruitReq.cs
@@ -111,30 +111,38 @@ public override FruitReq Read(ref Utf8JsonReader utf8JsonReader, Type typeToConv
         {
             int currentDepth = utf8JsonReader.CurrentDepth;
 
-            if (utf8JsonReader.TokenType != JsonTokenType.StartObject && utf8JsonReader.TokenType != JsonTokenType.StartArray)
-                throw new JsonException();
-
             JsonTokenType startingTokenType = utf8JsonReader.TokenType;
 
             AppleReq appleReq = default;
             BananaReq bananaReq = default;
 
-            Utf8JsonReader utf8JsonReaderOneOf = utf8JsonReader;
-            while (utf8JsonReaderOneOf.Read())
+            if (startingTokenType != JsonTokenType.StartObject && startingTokenType != JsonTokenType.StartArray)
             {
-                if (startingTokenType == JsonTokenType.StartObject && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndObject && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
-                    break;
-
-                if (startingTokenType == JsonTokenType.StartArray && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndArray && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
-                    break;
+                Utf8JsonReader utf8JsonReaderAppleReq = utf8JsonReader;
+                ClientUtils.TryDeserialize<AppleReq>(ref utf8JsonReaderAppleReq, jsonSerializerOptions, out appleReq);
 
-                if (utf8JsonReaderOneOf.TokenType == JsonTokenType.PropertyName && currentDepth == utf8JsonReaderOneOf.CurrentDepth - 1)
+                Utf8JsonReader utf8JsonReaderBananaReq = utf8JsonReader;
+                ClientUtils.TryDeserialize<BananaReq>(ref utf8JsonReaderBananaReq, jsonSerializerOptions, out bananaReq);
+            }
+            else
+            {
+                Utf8JsonReader utf8JsonReaderOneOf = utf8JsonReader;
+                while (utf8JsonReaderOneOf.Read())
                 {
-                    Utf8JsonReader utf8JsonReaderAppleReq = utf8JsonReader;
-                    ClientUtils.TryDeserialize<AppleReq>(ref utf8JsonReaderAppleReq, jsonSerializerOptions, out appleReq);
+                    if (startingTokenType == JsonTokenType.StartObject && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndObject && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
+                        break;
 
-                    Utf8JsonReader utf8JsonReaderBananaReq = utf8JsonReader;
-                    ClientUtils.TryDeserialize<BananaReq>(ref utf8JsonReaderBananaReq, jsonSerializerOptions, out bananaReq);
+                    if (startingTokenType == JsonTokenType.StartArray && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndArray && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
+                        break;
+
+                    if (utf8JsonReaderOneOf.TokenType == JsonTokenType.PropertyName && currentDepth == utf8JsonReaderOneOf.CurrentDepth - 1)
+                    {
+                        Utf8JsonReader utf8JsonReaderAppleReq = utf8JsonReader;
+                        ClientUtils.TryDeserialize<AppleReq>(ref utf8JsonReaderAppleReq, jsonSerializerOptions, out appleReq);
+
+                        Utf8JsonReader utf8JsonReaderBananaReq = utf8JsonReader;
+                        ClientUtils.TryDeserialize<BananaReq>(ref utf8JsonReaderBananaReq, jsonSerializerOptions, out bananaReq);
+                    }
                 }
             }
 
@@ -178,6 +186,17 @@ public override FruitReq Read(ref Utf8JsonReader utf8JsonReader, Type typeToConv
         public override void Write(Utf8JsonWriter writer, FruitReq fruitReq, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruitReq.AppleReq != null)
+            {
+                AppleReqJsonConverter appleReqJsonConverter = (AppleReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.AppleReq.GetType()));
+                appleReqJsonConverter.WriteProperties(writer, fruitReq.AppleReq, jsonSerializerOptions);
+            }
+
+            if (fruitReq.BananaReq != null)
+            {
+                BananaReqJsonConverter bananaReqJsonConverter = (BananaReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.BananaReq.GetType()));
+                bananaReqJsonConverter.WriteProperties(writer, fruitReq.BananaReq, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruitReq, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/Mammal.cs b/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/Mammal.cs
index 9bc6bbaaf9b9..887a0aa826cf 100644
--- a/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/Mammal.cs
+++ b/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/Mammal.cs
@@ -143,9 +143,6 @@ public override Mammal Read(ref Utf8JsonReader utf8JsonReader, Type typeToConver
         {
             int currentDepth = utf8JsonReader.CurrentDepth;
 
-            if (utf8JsonReader.TokenType != JsonTokenType.StartObject && utf8JsonReader.TokenType != JsonTokenType.StartArray)
-                throw new JsonException();
-
             JsonTokenType startingTokenType = utf8JsonReader.TokenType;
 
             Option<string> className = default;
diff --git a/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/MixedOneOfContent.cs b/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
index 88d0a9a352de..000f8dddd5cc 100644
--- a/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
+++ b/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
@@ -163,9 +163,6 @@ public override MixedOneOfContent Read(ref Utf8JsonReader utf8JsonReader, Type t
         {
             int currentDepth = utf8JsonReader.CurrentDepth;
 
-            if (utf8JsonReader.TokenType != JsonTokenType.StartObject && utf8JsonReader.TokenType != JsonTokenType.StartArray)
-                throw new JsonException();
-
             JsonTokenType startingTokenType = utf8JsonReader.TokenType;
 
             string varString = default;
@@ -174,31 +171,51 @@ public override MixedOneOfContent Read(ref Utf8JsonReader utf8JsonReader, Type t
             decimal? varDecimal = default;
             MixedSubId mixedSubId = default;
 
-            Utf8JsonReader utf8JsonReaderOneOf = utf8JsonReader;
-            while (utf8JsonReaderOneOf.Read())
+            if (startingTokenType != JsonTokenType.StartObject && startingTokenType != JsonTokenType.StartArray)
             {
-                if (startingTokenType == JsonTokenType.StartObject && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndObject && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
-                    break;
+                Utf8JsonReader utf8JsonReaderString = utf8JsonReader;
+                ClientUtils.TryDeserialize<string>(ref utf8JsonReaderString, jsonSerializerOptions, out varString);
 
-                if (startingTokenType == JsonTokenType.StartArray && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndArray && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
-                    break;
+                Utf8JsonReader utf8JsonReaderBool = utf8JsonReader;
+                ClientUtils.TryDeserialize<bool?>(ref utf8JsonReaderBool, jsonSerializerOptions, out varBool);
+
+                Utf8JsonReader utf8JsonReaderInt = utf8JsonReader;
+                ClientUtils.TryDeserialize<int?>(ref utf8JsonReaderInt, jsonSerializerOptions, out varInt);
 
-                if (utf8JsonReaderOneOf.TokenType == JsonTokenType.PropertyName && currentDepth == utf8JsonReaderOneOf.CurrentDepth - 1)
+                Utf8JsonReader utf8JsonReaderDecimal = utf8JsonReader;
+                ClientUtils.TryDeserialize<decimal?>(ref utf8JsonReaderDecimal, jsonSerializerOptions, out varDecimal);
+
+                Utf8JsonReader utf8JsonReaderMixedSubId = utf8JsonReader;
+                ClientUtils.TryDeserialize<MixedSubId>(ref utf8JsonReaderMixedSubId, jsonSerializerOptions, out mixedSubId);
+            }
+            else
+            {
+                Utf8JsonReader utf8JsonReaderOneOf = utf8JsonReader;
+                while (utf8JsonReaderOneOf.Read())
                 {
-                    Utf8JsonReader utf8JsonReaderString = utf8JsonReader;
-                    ClientUtils.TryDeserialize<string>(ref utf8JsonReaderString, jsonSerializerOptions, out varString);
+                    if (startingTokenType == JsonTokenType.StartObject && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndObject && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
+                        break;
 
-                    Utf8JsonReader utf8JsonReaderBool = utf8JsonReader;
-                    ClientUtils.TryDeserialize<bool?>(ref utf8JsonReaderBool, jsonSerializerOptions, out varBool);
+                    if (startingTokenType == JsonTokenType.StartArray && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndArray && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
+                        break;
 
-                    Utf8JsonReader utf8JsonReaderInt = utf8JsonReader;
-                    ClientUtils.TryDeserialize<int?>(ref utf8JsonReaderInt, jsonSerializerOptions, out varInt);
+                    if (utf8JsonReaderOneOf.TokenType == JsonTokenType.PropertyName && currentDepth == utf8JsonReaderOneOf.CurrentDepth - 1)
+                    {
+                        Utf8JsonReader utf8JsonReaderString = utf8JsonReader;
+                        ClientUtils.TryDeserialize<string>(ref utf8JsonReaderString, jsonSerializerOptions, out varString);
+
+                        Utf8JsonReader utf8JsonReaderBool = utf8JsonReader;
+                        ClientUtils.TryDeserialize<bool?>(ref utf8JsonReaderBool, jsonSerializerOptions, out varBool);
+
+                        Utf8JsonReader utf8JsonReaderInt = utf8JsonReader;
+                        ClientUtils.TryDeserialize<int?>(ref utf8JsonReaderInt, jsonSerializerOptions, out varInt);
 
-                    Utf8JsonReader utf8JsonReaderDecimal = utf8JsonReader;
-                    ClientUtils.TryDeserialize<decimal?>(ref utf8JsonReaderDecimal, jsonSerializerOptions, out varDecimal);
+                        Utf8JsonReader utf8JsonReaderDecimal = utf8JsonReader;
+                        ClientUtils.TryDeserialize<decimal?>(ref utf8JsonReaderDecimal, jsonSerializerOptions, out varDecimal);
 
-                    Utf8JsonReader utf8JsonReaderMixedSubId = utf8JsonReader;
-                    ClientUtils.TryDeserialize<MixedSubId>(ref utf8JsonReaderMixedSubId, jsonSerializerOptions, out mixedSubId);
+                        Utf8JsonReader utf8JsonReaderMixedSubId = utf8JsonReader;
+                        ClientUtils.TryDeserialize<MixedSubId>(ref utf8JsonReaderMixedSubId, jsonSerializerOptions, out mixedSubId);
+                    }
                 }
             }
 
@@ -250,7 +267,36 @@ public override MixedOneOfContent Read(ref Utf8JsonReader utf8JsonReader, Type t
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, MixedOneOfContent mixedOneOfContent, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (mixedOneOfContent.String != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Int != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Int, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Decimal != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Decimal, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
+            if (mixedOneOfContent.MixedSubId != null)
+            {
+                MixedSubIdJsonConverter mixedSubIdJsonConverter = (MixedSubIdJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(mixedOneOfContent.MixedSubId.GetType()));
+                mixedSubIdJsonConverter.WriteProperties(writer, mixedOneOfContent.MixedSubId, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, mixedOneOfContent, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/NullableShape.cs b/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/NullableShape.cs
index dd205b2df274..4b17a388c158 100644
--- a/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/NullableShape.cs
+++ b/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/NullableShape.cs
@@ -128,9 +128,6 @@ public override NullableShape Read(ref Utf8JsonReader utf8JsonReader, Type typeT
         {
             int currentDepth = utf8JsonReader.CurrentDepth;
 
-            if (utf8JsonReader.TokenType != JsonTokenType.StartObject && utf8JsonReader.TokenType != JsonTokenType.StartArray)
-                throw new JsonException();
-
             JsonTokenType startingTokenType = utf8JsonReader.TokenType;
 
             Option<string> shapeType = default;
diff --git a/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/OneOfString.cs b/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/OneOfString.cs
index af0ceaa278b0..abe2bb642287 100644
--- a/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/OneOfString.cs
+++ b/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/OneOfString.cs
@@ -103,9 +103,6 @@ public override OneOfString Read(ref Utf8JsonReader utf8JsonReader, Type typeToC
         {
             int currentDepth = utf8JsonReader.CurrentDepth;
 
-            if (utf8JsonReader.TokenType != JsonTokenType.StartObject && utf8JsonReader.TokenType != JsonTokenType.StartArray)
-                throw new JsonException();
-
             JsonTokenType startingTokenType = utf8JsonReader.TokenType;
 
             string varString = default;
@@ -146,6 +143,12 @@ public override OneOfString Read(ref Utf8JsonReader utf8JsonReader, Type typeToC
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, OneOfString oneOfString, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (oneOfString.String != null)
+            {
+                JsonSerializer.Serialize(writer, oneOfString.String, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, oneOfString, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/Pig.cs b/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/Pig.cs
index 3d7b78a18292..ec64315fb235 100644
--- a/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/Pig.cs
+++ b/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/Pig.cs
@@ -128,9 +128,6 @@ public override Pig Read(ref Utf8JsonReader utf8JsonReader, Type typeToConvert,
         {
             int currentDepth = utf8JsonReader.CurrentDepth;
 
-            if (utf8JsonReader.TokenType != JsonTokenType.StartObject && utf8JsonReader.TokenType != JsonTokenType.StartArray)
-                throw new JsonException();
-
             JsonTokenType startingTokenType = utf8JsonReader.TokenType;
 
             Option<string> className = default;
diff --git a/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/PolymorphicProperty.cs b/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
index befe6e02ec3a..6e4ff3f20b9c 100644
--- a/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
+++ b/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
@@ -148,9 +148,6 @@ public override PolymorphicProperty Read(ref Utf8JsonReader utf8JsonReader, Type
         {
             int currentDepth = utf8JsonReader.CurrentDepth;
 
-            if (utf8JsonReader.TokenType != JsonTokenType.StartObject && utf8JsonReader.TokenType != JsonTokenType.StartArray)
-                throw new JsonException();
-
             JsonTokenType startingTokenType = utf8JsonReader.TokenType;
 
             bool? varBool = default;
@@ -158,28 +155,45 @@ public override PolymorphicProperty Read(ref Utf8JsonReader utf8JsonReader, Type
             Object varObject = default;
             List<string> list = default;
 
-            Utf8JsonReader utf8JsonReaderOneOf = utf8JsonReader;
-            while (utf8JsonReaderOneOf.Read())
+            if (startingTokenType != JsonTokenType.StartObject && startingTokenType != JsonTokenType.StartArray)
             {
-                if (startingTokenType == JsonTokenType.StartObject && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndObject && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
-                    break;
+                Utf8JsonReader utf8JsonReaderBool = utf8JsonReader;
+                ClientUtils.TryDeserialize<bool?>(ref utf8JsonReaderBool, jsonSerializerOptions, out varBool);
 
-                if (startingTokenType == JsonTokenType.StartArray && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndArray && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
-                    break;
+                Utf8JsonReader utf8JsonReaderString = utf8JsonReader;
+                ClientUtils.TryDeserialize<string>(ref utf8JsonReaderString, jsonSerializerOptions, out varString);
 
-                if (utf8JsonReaderOneOf.TokenType == JsonTokenType.PropertyName && currentDepth == utf8JsonReaderOneOf.CurrentDepth - 1)
+                Utf8JsonReader utf8JsonReaderObject = utf8JsonReader;
+                ClientUtils.TryDeserialize<Object>(ref utf8JsonReaderObject, jsonSerializerOptions, out varObject);
+
+                Utf8JsonReader utf8JsonReaderList = utf8JsonReader;
+                ClientUtils.TryDeserialize<List<string>>(ref utf8JsonReaderList, jsonSerializerOptions, out list);
+            }
+            else
+            {
+                Utf8JsonReader utf8JsonReaderOneOf = utf8JsonReader;
+                while (utf8JsonReaderOneOf.Read())
                 {
-                    Utf8JsonReader utf8JsonReaderBool = utf8JsonReader;
-                    ClientUtils.TryDeserialize<bool?>(ref utf8JsonReaderBool, jsonSerializerOptions, out varBool);
+                    if (startingTokenType == JsonTokenType.StartObject && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndObject && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
+                        break;
 
-                    Utf8JsonReader utf8JsonReaderString = utf8JsonReader;
-                    ClientUtils.TryDeserialize<string>(ref utf8JsonReaderString, jsonSerializerOptions, out varString);
+                    if (startingTokenType == JsonTokenType.StartArray && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndArray && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
+                        break;
 
-                    Utf8JsonReader utf8JsonReaderObject = utf8JsonReader;
-                    ClientUtils.TryDeserialize<Object>(ref utf8JsonReaderObject, jsonSerializerOptions, out varObject);
+                    if (utf8JsonReaderOneOf.TokenType == JsonTokenType.PropertyName && currentDepth == utf8JsonReaderOneOf.CurrentDepth - 1)
+                    {
+                        Utf8JsonReader utf8JsonReaderBool = utf8JsonReader;
+                        ClientUtils.TryDeserialize<bool?>(ref utf8JsonReaderBool, jsonSerializerOptions, out varBool);
+
+                        Utf8JsonReader utf8JsonReaderString = utf8JsonReader;
+                        ClientUtils.TryDeserialize<string>(ref utf8JsonReaderString, jsonSerializerOptions, out varString);
+
+                        Utf8JsonReader utf8JsonReaderObject = utf8JsonReader;
+                        ClientUtils.TryDeserialize<Object>(ref utf8JsonReaderObject, jsonSerializerOptions, out varObject);
 
-                    Utf8JsonReader utf8JsonReaderList = utf8JsonReader;
-                    ClientUtils.TryDeserialize<List<string>>(ref utf8JsonReaderList, jsonSerializerOptions, out list);
+                        Utf8JsonReader utf8JsonReaderList = utf8JsonReader;
+                        ClientUtils.TryDeserialize<List<string>>(ref utf8JsonReaderList, jsonSerializerOptions, out list);
+                    }
                 }
             }
 
@@ -228,6 +242,30 @@ public override PolymorphicProperty Read(ref Utf8JsonReader utf8JsonReader, Type
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, PolymorphicProperty polymorphicProperty, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (polymorphicProperty.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.String != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.Object != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Object, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.List != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.List, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, polymorphicProperty, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/Quadrilateral.cs b/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/Quadrilateral.cs
index f1b8095c949f..2381d0df3f1e 100644
--- a/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/Quadrilateral.cs
+++ b/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/Quadrilateral.cs
@@ -128,9 +128,6 @@ public override Quadrilateral Read(ref Utf8JsonReader utf8JsonReader, Type typeT
         {
             int currentDepth = utf8JsonReader.CurrentDepth;
 
-            if (utf8JsonReader.TokenType != JsonTokenType.StartObject && utf8JsonReader.TokenType != JsonTokenType.StartArray)
-                throw new JsonException();
-
             JsonTokenType startingTokenType = utf8JsonReader.TokenType;
 
             Option<string> quadrilateralType = default;
diff --git a/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/Shape.cs b/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/Shape.cs
index 7a2dd62962fb..d230cf0bb29c 100644
--- a/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/Shape.cs
+++ b/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/Shape.cs
@@ -128,9 +128,6 @@ public override Shape Read(ref Utf8JsonReader utf8JsonReader, Type typeToConvert
         {
             int currentDepth = utf8JsonReader.CurrentDepth;
 
-            if (utf8JsonReader.TokenType != JsonTokenType.StartObject && utf8JsonReader.TokenType != JsonTokenType.StartArray)
-                throw new JsonException();
-
             JsonTokenType startingTokenType = utf8JsonReader.TokenType;
 
             Option<string> shapeType = default;
diff --git a/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/ShapeOrNull.cs b/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/ShapeOrNull.cs
index 52a892aeb9e1..30d965bad4c6 100644
--- a/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/ShapeOrNull.cs
+++ b/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/ShapeOrNull.cs
@@ -128,9 +128,6 @@ public override ShapeOrNull Read(ref Utf8JsonReader utf8JsonReader, Type typeToC
         {
             int currentDepth = utf8JsonReader.CurrentDepth;
 
-            if (utf8JsonReader.TokenType != JsonTokenType.StartObject && utf8JsonReader.TokenType != JsonTokenType.StartArray)
-                throw new JsonException();
-
             JsonTokenType startingTokenType = utf8JsonReader.TokenType;
 
             Option<string> shapeType = default;
diff --git a/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/Triangle.cs b/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/Triangle.cs
index 9e1ae42200c6..96859dae2927 100644
--- a/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/Triangle.cs
+++ b/samples/client/petstore/csharp/generichost/net8/FormModels/src/Org.OpenAPITools/Model/Triangle.cs
@@ -143,9 +143,6 @@ public override Triangle Read(ref Utf8JsonReader utf8JsonReader, Type typeToConv
         {
             int currentDepth = utf8JsonReader.CurrentDepth;
 
-            if (utf8JsonReader.TokenType != JsonTokenType.StartObject && utf8JsonReader.TokenType != JsonTokenType.StartArray)
-                throw new JsonException();
-
             JsonTokenType startingTokenType = utf8JsonReader.TokenType;
 
             Option<string> triangleType = default;
diff --git a/samples/client/petstore/csharp/generichost/net8/NullReferenceTypes/src/Org.OpenAPITools/Model/Fruit.cs b/samples/client/petstore/csharp/generichost/net8/NullReferenceTypes/src/Org.OpenAPITools/Model/Fruit.cs
index ec0062ba20d3..67cb3b13af6c 100644
--- a/samples/client/petstore/csharp/generichost/net8/NullReferenceTypes/src/Org.OpenAPITools/Model/Fruit.cs
+++ b/samples/client/petstore/csharp/generichost/net8/NullReferenceTypes/src/Org.OpenAPITools/Model/Fruit.cs
@@ -206,6 +206,17 @@ public override Fruit Read(ref Utf8JsonReader utf8JsonReader, Type typeToConvert
         public override void Write(Utf8JsonWriter writer, Fruit fruit, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruit.Apple != null)
+            {
+                AppleJsonConverter appleJsonConverter = (AppleJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Apple.GetType()));
+                appleJsonConverter.WriteProperties(writer, fruit.Apple, jsonSerializerOptions);
+            }
+
+            if (fruit.Banana != null)
+            {
+                BananaJsonConverter bananaJsonConverter = (BananaJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Banana.GetType()));
+                bananaJsonConverter.WriteProperties(writer, fruit.Banana, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruit, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net8/NullReferenceTypes/src/Org.OpenAPITools/Model/FruitReq.cs b/samples/client/petstore/csharp/generichost/net8/NullReferenceTypes/src/Org.OpenAPITools/Model/FruitReq.cs
index af1802aab1a9..d73d15fdc718 100644
--- a/samples/client/petstore/csharp/generichost/net8/NullReferenceTypes/src/Org.OpenAPITools/Model/FruitReq.cs
+++ b/samples/client/petstore/csharp/generichost/net8/NullReferenceTypes/src/Org.OpenAPITools/Model/FruitReq.cs
@@ -180,6 +180,17 @@ public override FruitReq Read(ref Utf8JsonReader utf8JsonReader, Type typeToConv
         public override void Write(Utf8JsonWriter writer, FruitReq fruitReq, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruitReq.AppleReq != null)
+            {
+                AppleReqJsonConverter appleReqJsonConverter = (AppleReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.AppleReq.GetType()));
+                appleReqJsonConverter.WriteProperties(writer, fruitReq.AppleReq, jsonSerializerOptions);
+            }
+
+            if (fruitReq.BananaReq != null)
+            {
+                BananaReqJsonConverter bananaReqJsonConverter = (BananaReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.BananaReq.GetType()));
+                bananaReqJsonConverter.WriteProperties(writer, fruitReq.BananaReq, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruitReq, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net8/NullReferenceTypes/src/Org.OpenAPITools/Model/MixedOneOfContent.cs b/samples/client/petstore/csharp/generichost/net8/NullReferenceTypes/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
index bac36e3cbe70..2b27c5610dad 100644
--- a/samples/client/petstore/csharp/generichost/net8/NullReferenceTypes/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
+++ b/samples/client/petstore/csharp/generichost/net8/NullReferenceTypes/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
@@ -252,7 +252,36 @@ public override MixedOneOfContent Read(ref Utf8JsonReader utf8JsonReader, Type t
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, MixedOneOfContent mixedOneOfContent, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (mixedOneOfContent.String != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Int != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Int, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Decimal != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Decimal, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
+            if (mixedOneOfContent.MixedSubId != null)
+            {
+                MixedSubIdJsonConverter mixedSubIdJsonConverter = (MixedSubIdJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(mixedOneOfContent.MixedSubId.GetType()));
+                mixedSubIdJsonConverter.WriteProperties(writer, mixedOneOfContent.MixedSubId, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, mixedOneOfContent, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net8/NullReferenceTypes/src/Org.OpenAPITools/Model/OneOfString.cs b/samples/client/petstore/csharp/generichost/net8/NullReferenceTypes/src/Org.OpenAPITools/Model/OneOfString.cs
index e03117058c32..50b6a7869b9f 100644
--- a/samples/client/petstore/csharp/generichost/net8/NullReferenceTypes/src/Org.OpenAPITools/Model/OneOfString.cs
+++ b/samples/client/petstore/csharp/generichost/net8/NullReferenceTypes/src/Org.OpenAPITools/Model/OneOfString.cs
@@ -148,6 +148,12 @@ public override OneOfString Read(ref Utf8JsonReader utf8JsonReader, Type typeToC
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, OneOfString oneOfString, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (oneOfString.String != null)
+            {
+                JsonSerializer.Serialize(writer, oneOfString.String, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, oneOfString, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/net8/NullReferenceTypes/src/Org.OpenAPITools/Model/PolymorphicProperty.cs b/samples/client/petstore/csharp/generichost/net8/NullReferenceTypes/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
index d33ed7654562..6aeb2e63b84d 100644
--- a/samples/client/petstore/csharp/generichost/net8/NullReferenceTypes/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
+++ b/samples/client/petstore/csharp/generichost/net8/NullReferenceTypes/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
@@ -230,6 +230,30 @@ public override PolymorphicProperty Read(ref Utf8JsonReader utf8JsonReader, Type
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, PolymorphicProperty polymorphicProperty, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (polymorphicProperty.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.String != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.Object != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Object, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.List != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.List, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, polymorphicProperty, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/net8/OneOf/src/Org.OpenAPITools.Test/Model/FruitTests.cs b/samples/client/petstore/csharp/generichost/net8/OneOf/src/Org.OpenAPITools.Test/Model/FruitTests.cs
index a6607ae5d56d..8eb2a2d59126 100644
--- a/samples/client/petstore/csharp/generichost/net8/OneOf/src/Org.OpenAPITools.Test/Model/FruitTests.cs
+++ b/samples/client/petstore/csharp/generichost/net8/OneOf/src/Org.OpenAPITools.Test/Model/FruitTests.cs
@@ -17,6 +17,7 @@
 using Org.OpenAPITools.Model;
 using Org.OpenAPITools.Client;
 using System.Reflection;
+using System.Text.Json;
 
 namespace Org.OpenAPITools.Test.Model
 {
@@ -61,5 +62,40 @@ public void ColorTest()
         {
             // TODO unit test for the property 'Color'
         }
+
+        [Fact]
+        public void SerializeOneOfReferencedObject()
+        {
+            var options = new JsonSerializerOptions();
+            options.Converters.Add(new AppleJsonConverter());
+            options.Converters.Add(new BananaJsonConverter());
+            options.Converters.Add(new FruitJsonConverter());
+            options.Converters.Add(new OrangeJsonConverter());
+
+            Fruit fruit = new Fruit(new Apple("red"));
+
+            string json = JsonSerializer.Serialize(fruit, options);
+
+            Assert.Equal("{\"kind\":\"red\"}", json);
+        }
+
+        [Fact]
+        public void SerializeOneOfReferencedObjectWithSiblingProperty()
+        {
+            var options = new JsonSerializerOptions();
+            options.Converters.Add(new AppleJsonConverter());
+            options.Converters.Add(new BananaJsonConverter());
+            options.Converters.Add(new FruitJsonConverter());
+            options.Converters.Add(new OrangeJsonConverter());
+
+            Fruit fruit = new Fruit(
+                new Apple("red"),
+                new Option<string?>("green")
+            );
+
+            string json = JsonSerializer.Serialize(fruit, options);
+
+            Assert.Equal("{\"kind\":\"red\",\"color\":\"green\"}", json);
+        }
     }
 }
diff --git a/samples/client/petstore/csharp/generichost/net8/OneOf/src/Org.OpenAPITools/Model/Fruit.cs b/samples/client/petstore/csharp/generichost/net8/OneOf/src/Org.OpenAPITools/Model/Fruit.cs
index 1a4743015087..be03ed7e708e 100644
--- a/samples/client/petstore/csharp/generichost/net8/OneOf/src/Org.OpenAPITools/Model/Fruit.cs
+++ b/samples/client/petstore/csharp/generichost/net8/OneOf/src/Org.OpenAPITools/Model/Fruit.cs
@@ -237,6 +237,23 @@ public override Fruit Read(ref Utf8JsonReader utf8JsonReader, Type typeToConvert
         public override void Write(Utf8JsonWriter writer, Fruit fruit, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruit.Apple != null)
+            {
+                AppleJsonConverter appleJsonConverter = (AppleJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Apple.GetType()));
+                appleJsonConverter.WriteProperties(writer, fruit.Apple, jsonSerializerOptions);
+            }
+
+            if (fruit.Banana != null)
+            {
+                BananaJsonConverter bananaJsonConverter = (BananaJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Banana.GetType()));
+                bananaJsonConverter.WriteProperties(writer, fruit.Banana, jsonSerializerOptions);
+            }
+
+            if (fruit.Orange != null)
+            {
+                OrangeJsonConverter orangeJsonConverter = (OrangeJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Orange.GetType()));
+                orangeJsonConverter.WriteProperties(writer, fruit.Orange, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruit, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net8/Petstore/src/Org.OpenAPITools/Model/Fruit.cs b/samples/client/petstore/csharp/generichost/net8/Petstore/src/Org.OpenAPITools/Model/Fruit.cs
index ca703d27f96c..523e4981cf08 100644
--- a/samples/client/petstore/csharp/generichost/net8/Petstore/src/Org.OpenAPITools/Model/Fruit.cs
+++ b/samples/client/petstore/csharp/generichost/net8/Petstore/src/Org.OpenAPITools/Model/Fruit.cs
@@ -204,6 +204,17 @@ public override Fruit Read(ref Utf8JsonReader utf8JsonReader, Type typeToConvert
         public override void Write(Utf8JsonWriter writer, Fruit fruit, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruit.Apple != null)
+            {
+                AppleJsonConverter appleJsonConverter = (AppleJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Apple.GetType()));
+                appleJsonConverter.WriteProperties(writer, fruit.Apple, jsonSerializerOptions);
+            }
+
+            if (fruit.Banana != null)
+            {
+                BananaJsonConverter bananaJsonConverter = (BananaJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Banana.GetType()));
+                bananaJsonConverter.WriteProperties(writer, fruit.Banana, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruit, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net8/Petstore/src/Org.OpenAPITools/Model/FruitReq.cs b/samples/client/petstore/csharp/generichost/net8/Petstore/src/Org.OpenAPITools/Model/FruitReq.cs
index 440fbefb11ac..ac498f51caf9 100644
--- a/samples/client/petstore/csharp/generichost/net8/Petstore/src/Org.OpenAPITools/Model/FruitReq.cs
+++ b/samples/client/petstore/csharp/generichost/net8/Petstore/src/Org.OpenAPITools/Model/FruitReq.cs
@@ -178,6 +178,17 @@ public override FruitReq Read(ref Utf8JsonReader utf8JsonReader, Type typeToConv
         public override void Write(Utf8JsonWriter writer, FruitReq fruitReq, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruitReq.AppleReq != null)
+            {
+                AppleReqJsonConverter appleReqJsonConverter = (AppleReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.AppleReq.GetType()));
+                appleReqJsonConverter.WriteProperties(writer, fruitReq.AppleReq, jsonSerializerOptions);
+            }
+
+            if (fruitReq.BananaReq != null)
+            {
+                BananaReqJsonConverter bananaReqJsonConverter = (BananaReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.BananaReq.GetType()));
+                bananaReqJsonConverter.WriteProperties(writer, fruitReq.BananaReq, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruitReq, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net8/Petstore/src/Org.OpenAPITools/Model/MixedOneOfContent.cs b/samples/client/petstore/csharp/generichost/net8/Petstore/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
index 88d0a9a352de..270d653642cd 100644
--- a/samples/client/petstore/csharp/generichost/net8/Petstore/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
+++ b/samples/client/petstore/csharp/generichost/net8/Petstore/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
@@ -250,7 +250,36 @@ public override MixedOneOfContent Read(ref Utf8JsonReader utf8JsonReader, Type t
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, MixedOneOfContent mixedOneOfContent, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (mixedOneOfContent.String != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Int != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Int, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Decimal != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Decimal, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
+            if (mixedOneOfContent.MixedSubId != null)
+            {
+                MixedSubIdJsonConverter mixedSubIdJsonConverter = (MixedSubIdJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(mixedOneOfContent.MixedSubId.GetType()));
+                mixedSubIdJsonConverter.WriteProperties(writer, mixedOneOfContent.MixedSubId, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, mixedOneOfContent, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net8/Petstore/src/Org.OpenAPITools/Model/OneOfString.cs b/samples/client/petstore/csharp/generichost/net8/Petstore/src/Org.OpenAPITools/Model/OneOfString.cs
index af0ceaa278b0..b5b0a324b1eb 100644
--- a/samples/client/petstore/csharp/generichost/net8/Petstore/src/Org.OpenAPITools/Model/OneOfString.cs
+++ b/samples/client/petstore/csharp/generichost/net8/Petstore/src/Org.OpenAPITools/Model/OneOfString.cs
@@ -146,6 +146,12 @@ public override OneOfString Read(ref Utf8JsonReader utf8JsonReader, Type typeToC
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, OneOfString oneOfString, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (oneOfString.String != null)
+            {
+                JsonSerializer.Serialize(writer, oneOfString.String, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, oneOfString, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/net8/Petstore/src/Org.OpenAPITools/Model/PolymorphicProperty.cs b/samples/client/petstore/csharp/generichost/net8/Petstore/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
index befe6e02ec3a..c7ef5eda6387 100644
--- a/samples/client/petstore/csharp/generichost/net8/Petstore/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
+++ b/samples/client/petstore/csharp/generichost/net8/Petstore/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
@@ -228,6 +228,30 @@ public override PolymorphicProperty Read(ref Utf8JsonReader utf8JsonReader, Type
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, PolymorphicProperty polymorphicProperty, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (polymorphicProperty.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.String != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.Object != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Object, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.List != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.List, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, polymorphicProperty, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/net8/SourceGeneration/src/Org.OpenAPITools/Model/Fruit.cs b/samples/client/petstore/csharp/generichost/net8/SourceGeneration/src/Org.OpenAPITools/Model/Fruit.cs
index 9bad6c70417c..8e385da82a91 100644
--- a/samples/client/petstore/csharp/generichost/net8/SourceGeneration/src/Org.OpenAPITools/Model/Fruit.cs
+++ b/samples/client/petstore/csharp/generichost/net8/SourceGeneration/src/Org.OpenAPITools/Model/Fruit.cs
@@ -207,6 +207,17 @@ public override Fruit Read(ref Utf8JsonReader utf8JsonReader, Type typeToConvert
         public override void Write(Utf8JsonWriter writer, Fruit fruit, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruit.Apple != null)
+            {
+                AppleJsonConverter appleJsonConverter = (AppleJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Apple.GetType()));
+                appleJsonConverter.WriteProperties(writer, fruit.Apple, jsonSerializerOptions);
+            }
+
+            if (fruit.Banana != null)
+            {
+                BananaJsonConverter bananaJsonConverter = (BananaJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Banana.GetType()));
+                bananaJsonConverter.WriteProperties(writer, fruit.Banana, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruit, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net8/SourceGeneration/src/Org.OpenAPITools/Model/FruitReq.cs b/samples/client/petstore/csharp/generichost/net8/SourceGeneration/src/Org.OpenAPITools/Model/FruitReq.cs
index ed5e1e35c028..361da9371288 100644
--- a/samples/client/petstore/csharp/generichost/net8/SourceGeneration/src/Org.OpenAPITools/Model/FruitReq.cs
+++ b/samples/client/petstore/csharp/generichost/net8/SourceGeneration/src/Org.OpenAPITools/Model/FruitReq.cs
@@ -181,6 +181,17 @@ public override FruitReq Read(ref Utf8JsonReader utf8JsonReader, Type typeToConv
         public override void Write(Utf8JsonWriter writer, FruitReq fruitReq, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruitReq.AppleReq != null)
+            {
+                AppleReqJsonConverter appleReqJsonConverter = (AppleReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.AppleReq.GetType()));
+                appleReqJsonConverter.WriteProperties(writer, fruitReq.AppleReq, jsonSerializerOptions);
+            }
+
+            if (fruitReq.BananaReq != null)
+            {
+                BananaReqJsonConverter bananaReqJsonConverter = (BananaReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.BananaReq.GetType()));
+                bananaReqJsonConverter.WriteProperties(writer, fruitReq.BananaReq, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruitReq, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net8/SourceGeneration/src/Org.OpenAPITools/Model/MixedOneOfContent.cs b/samples/client/petstore/csharp/generichost/net8/SourceGeneration/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
index ca6ca27187dd..c96886067b6b 100644
--- a/samples/client/petstore/csharp/generichost/net8/SourceGeneration/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
+++ b/samples/client/petstore/csharp/generichost/net8/SourceGeneration/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
@@ -253,7 +253,36 @@ public override MixedOneOfContent Read(ref Utf8JsonReader utf8JsonReader, Type t
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, MixedOneOfContent mixedOneOfContent, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (mixedOneOfContent.String != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Int != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Int, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Decimal != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Decimal, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
+            if (mixedOneOfContent.MixedSubId != null)
+            {
+                MixedSubIdJsonConverter mixedSubIdJsonConverter = (MixedSubIdJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(mixedOneOfContent.MixedSubId.GetType()));
+                mixedSubIdJsonConverter.WriteProperties(writer, mixedOneOfContent.MixedSubId, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, mixedOneOfContent, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net8/SourceGeneration/src/Org.OpenAPITools/Model/OneOfString.cs b/samples/client/petstore/csharp/generichost/net8/SourceGeneration/src/Org.OpenAPITools/Model/OneOfString.cs
index 4a46f52ead3a..df1341c55fed 100644
--- a/samples/client/petstore/csharp/generichost/net8/SourceGeneration/src/Org.OpenAPITools/Model/OneOfString.cs
+++ b/samples/client/petstore/csharp/generichost/net8/SourceGeneration/src/Org.OpenAPITools/Model/OneOfString.cs
@@ -149,6 +149,12 @@ public override OneOfString Read(ref Utf8JsonReader utf8JsonReader, Type typeToC
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, OneOfString oneOfString, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (oneOfString.String != null)
+            {
+                JsonSerializer.Serialize(writer, oneOfString.String, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, oneOfString, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/net8/SourceGeneration/src/Org.OpenAPITools/Model/PolymorphicProperty.cs b/samples/client/petstore/csharp/generichost/net8/SourceGeneration/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
index d3e959b95a67..114391721fd3 100644
--- a/samples/client/petstore/csharp/generichost/net8/SourceGeneration/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
+++ b/samples/client/petstore/csharp/generichost/net8/SourceGeneration/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
@@ -231,6 +231,30 @@ public override PolymorphicProperty Read(ref Utf8JsonReader utf8JsonReader, Type
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, PolymorphicProperty polymorphicProperty, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (polymorphicProperty.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.String != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.Object != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Object, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.List != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.List, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, polymorphicProperty, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/Fruit.cs b/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/Fruit.cs
index ca703d27f96c..c9638e5b9882 100644
--- a/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/Fruit.cs
+++ b/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/Fruit.cs
@@ -129,9 +129,6 @@ public override Fruit Read(ref Utf8JsonReader utf8JsonReader, Type typeToConvert
         {
             int currentDepth = utf8JsonReader.CurrentDepth;
 
-            if (utf8JsonReader.TokenType != JsonTokenType.StartObject && utf8JsonReader.TokenType != JsonTokenType.StartArray)
-                throw new JsonException();
-
             JsonTokenType startingTokenType = utf8JsonReader.TokenType;
 
             Option<string> color = default;
@@ -139,22 +136,33 @@ public override Fruit Read(ref Utf8JsonReader utf8JsonReader, Type typeToConvert
             Apple apple = default;
             Banana banana = default;
 
-            Utf8JsonReader utf8JsonReaderOneOf = utf8JsonReader;
-            while (utf8JsonReaderOneOf.Read())
+            if (startingTokenType != JsonTokenType.StartObject && startingTokenType != JsonTokenType.StartArray)
             {
-                if (startingTokenType == JsonTokenType.StartObject && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndObject && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
-                    break;
-
-                if (startingTokenType == JsonTokenType.StartArray && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndArray && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
-                    break;
+                Utf8JsonReader utf8JsonReaderApple = utf8JsonReader;
+                ClientUtils.TryDeserialize<Apple>(ref utf8JsonReaderApple, jsonSerializerOptions, out apple);
 
-                if (utf8JsonReaderOneOf.TokenType == JsonTokenType.PropertyName && currentDepth == utf8JsonReaderOneOf.CurrentDepth - 1)
+                Utf8JsonReader utf8JsonReaderBanana = utf8JsonReader;
+                ClientUtils.TryDeserialize<Banana>(ref utf8JsonReaderBanana, jsonSerializerOptions, out banana);
+            }
+            else
+            {
+                Utf8JsonReader utf8JsonReaderOneOf = utf8JsonReader;
+                while (utf8JsonReaderOneOf.Read())
                 {
-                    Utf8JsonReader utf8JsonReaderApple = utf8JsonReader;
-                    ClientUtils.TryDeserialize<Apple>(ref utf8JsonReaderApple, jsonSerializerOptions, out apple);
+                    if (startingTokenType == JsonTokenType.StartObject && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndObject && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
+                        break;
 
-                    Utf8JsonReader utf8JsonReaderBanana = utf8JsonReader;
-                    ClientUtils.TryDeserialize<Banana>(ref utf8JsonReaderBanana, jsonSerializerOptions, out banana);
+                    if (startingTokenType == JsonTokenType.StartArray && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndArray && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
+                        break;
+
+                    if (utf8JsonReaderOneOf.TokenType == JsonTokenType.PropertyName && currentDepth == utf8JsonReaderOneOf.CurrentDepth - 1)
+                    {
+                        Utf8JsonReader utf8JsonReaderApple = utf8JsonReader;
+                        ClientUtils.TryDeserialize<Apple>(ref utf8JsonReaderApple, jsonSerializerOptions, out apple);
+
+                        Utf8JsonReader utf8JsonReaderBanana = utf8JsonReader;
+                        ClientUtils.TryDeserialize<Banana>(ref utf8JsonReaderBanana, jsonSerializerOptions, out banana);
+                    }
                 }
             }
 
@@ -204,6 +212,17 @@ public override Fruit Read(ref Utf8JsonReader utf8JsonReader, Type typeToConvert
         public override void Write(Utf8JsonWriter writer, Fruit fruit, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruit.Apple != null)
+            {
+                AppleJsonConverter appleJsonConverter = (AppleJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Apple.GetType()));
+                appleJsonConverter.WriteProperties(writer, fruit.Apple, jsonSerializerOptions);
+            }
+
+            if (fruit.Banana != null)
+            {
+                BananaJsonConverter bananaJsonConverter = (BananaJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Banana.GetType()));
+                bananaJsonConverter.WriteProperties(writer, fruit.Banana, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruit, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/FruitReq.cs b/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/FruitReq.cs
index 440fbefb11ac..2bb8e810357b 100644
--- a/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/FruitReq.cs
+++ b/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/FruitReq.cs
@@ -111,30 +111,38 @@ public override FruitReq Read(ref Utf8JsonReader utf8JsonReader, Type typeToConv
         {
             int currentDepth = utf8JsonReader.CurrentDepth;
 
-            if (utf8JsonReader.TokenType != JsonTokenType.StartObject && utf8JsonReader.TokenType != JsonTokenType.StartArray)
-                throw new JsonException();
-
             JsonTokenType startingTokenType = utf8JsonReader.TokenType;
 
             AppleReq appleReq = default;
             BananaReq bananaReq = default;
 
-            Utf8JsonReader utf8JsonReaderOneOf = utf8JsonReader;
-            while (utf8JsonReaderOneOf.Read())
+            if (startingTokenType != JsonTokenType.StartObject && startingTokenType != JsonTokenType.StartArray)
             {
-                if (startingTokenType == JsonTokenType.StartObject && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndObject && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
-                    break;
-
-                if (startingTokenType == JsonTokenType.StartArray && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndArray && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
-                    break;
+                Utf8JsonReader utf8JsonReaderAppleReq = utf8JsonReader;
+                ClientUtils.TryDeserialize<AppleReq>(ref utf8JsonReaderAppleReq, jsonSerializerOptions, out appleReq);
 
-                if (utf8JsonReaderOneOf.TokenType == JsonTokenType.PropertyName && currentDepth == utf8JsonReaderOneOf.CurrentDepth - 1)
+                Utf8JsonReader utf8JsonReaderBananaReq = utf8JsonReader;
+                ClientUtils.TryDeserialize<BananaReq>(ref utf8JsonReaderBananaReq, jsonSerializerOptions, out bananaReq);
+            }
+            else
+            {
+                Utf8JsonReader utf8JsonReaderOneOf = utf8JsonReader;
+                while (utf8JsonReaderOneOf.Read())
                 {
-                    Utf8JsonReader utf8JsonReaderAppleReq = utf8JsonReader;
-                    ClientUtils.TryDeserialize<AppleReq>(ref utf8JsonReaderAppleReq, jsonSerializerOptions, out appleReq);
+                    if (startingTokenType == JsonTokenType.StartObject && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndObject && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
+                        break;
 
-                    Utf8JsonReader utf8JsonReaderBananaReq = utf8JsonReader;
-                    ClientUtils.TryDeserialize<BananaReq>(ref utf8JsonReaderBananaReq, jsonSerializerOptions, out bananaReq);
+                    if (startingTokenType == JsonTokenType.StartArray && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndArray && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
+                        break;
+
+                    if (utf8JsonReaderOneOf.TokenType == JsonTokenType.PropertyName && currentDepth == utf8JsonReaderOneOf.CurrentDepth - 1)
+                    {
+                        Utf8JsonReader utf8JsonReaderAppleReq = utf8JsonReader;
+                        ClientUtils.TryDeserialize<AppleReq>(ref utf8JsonReaderAppleReq, jsonSerializerOptions, out appleReq);
+
+                        Utf8JsonReader utf8JsonReaderBananaReq = utf8JsonReader;
+                        ClientUtils.TryDeserialize<BananaReq>(ref utf8JsonReaderBananaReq, jsonSerializerOptions, out bananaReq);
+                    }
                 }
             }
 
@@ -178,6 +186,17 @@ public override FruitReq Read(ref Utf8JsonReader utf8JsonReader, Type typeToConv
         public override void Write(Utf8JsonWriter writer, FruitReq fruitReq, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruitReq.AppleReq != null)
+            {
+                AppleReqJsonConverter appleReqJsonConverter = (AppleReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.AppleReq.GetType()));
+                appleReqJsonConverter.WriteProperties(writer, fruitReq.AppleReq, jsonSerializerOptions);
+            }
+
+            if (fruitReq.BananaReq != null)
+            {
+                BananaReqJsonConverter bananaReqJsonConverter = (BananaReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.BananaReq.GetType()));
+                bananaReqJsonConverter.WriteProperties(writer, fruitReq.BananaReq, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruitReq, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/Mammal.cs b/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/Mammal.cs
index 9bc6bbaaf9b9..887a0aa826cf 100644
--- a/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/Mammal.cs
+++ b/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/Mammal.cs
@@ -143,9 +143,6 @@ public override Mammal Read(ref Utf8JsonReader utf8JsonReader, Type typeToConver
         {
             int currentDepth = utf8JsonReader.CurrentDepth;
 
-            if (utf8JsonReader.TokenType != JsonTokenType.StartObject && utf8JsonReader.TokenType != JsonTokenType.StartArray)
-                throw new JsonException();
-
             JsonTokenType startingTokenType = utf8JsonReader.TokenType;
 
             Option<string> className = default;
diff --git a/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/MixedOneOfContent.cs b/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
index 88d0a9a352de..000f8dddd5cc 100644
--- a/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
+++ b/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
@@ -163,9 +163,6 @@ public override MixedOneOfContent Read(ref Utf8JsonReader utf8JsonReader, Type t
         {
             int currentDepth = utf8JsonReader.CurrentDepth;
 
-            if (utf8JsonReader.TokenType != JsonTokenType.StartObject && utf8JsonReader.TokenType != JsonTokenType.StartArray)
-                throw new JsonException();
-
             JsonTokenType startingTokenType = utf8JsonReader.TokenType;
 
             string varString = default;
@@ -174,31 +171,51 @@ public override MixedOneOfContent Read(ref Utf8JsonReader utf8JsonReader, Type t
             decimal? varDecimal = default;
             MixedSubId mixedSubId = default;
 
-            Utf8JsonReader utf8JsonReaderOneOf = utf8JsonReader;
-            while (utf8JsonReaderOneOf.Read())
+            if (startingTokenType != JsonTokenType.StartObject && startingTokenType != JsonTokenType.StartArray)
             {
-                if (startingTokenType == JsonTokenType.StartObject && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndObject && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
-                    break;
+                Utf8JsonReader utf8JsonReaderString = utf8JsonReader;
+                ClientUtils.TryDeserialize<string>(ref utf8JsonReaderString, jsonSerializerOptions, out varString);
 
-                if (startingTokenType == JsonTokenType.StartArray && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndArray && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
-                    break;
+                Utf8JsonReader utf8JsonReaderBool = utf8JsonReader;
+                ClientUtils.TryDeserialize<bool?>(ref utf8JsonReaderBool, jsonSerializerOptions, out varBool);
+
+                Utf8JsonReader utf8JsonReaderInt = utf8JsonReader;
+                ClientUtils.TryDeserialize<int?>(ref utf8JsonReaderInt, jsonSerializerOptions, out varInt);
 
-                if (utf8JsonReaderOneOf.TokenType == JsonTokenType.PropertyName && currentDepth == utf8JsonReaderOneOf.CurrentDepth - 1)
+                Utf8JsonReader utf8JsonReaderDecimal = utf8JsonReader;
+                ClientUtils.TryDeserialize<decimal?>(ref utf8JsonReaderDecimal, jsonSerializerOptions, out varDecimal);
+
+                Utf8JsonReader utf8JsonReaderMixedSubId = utf8JsonReader;
+                ClientUtils.TryDeserialize<MixedSubId>(ref utf8JsonReaderMixedSubId, jsonSerializerOptions, out mixedSubId);
+            }
+            else
+            {
+                Utf8JsonReader utf8JsonReaderOneOf = utf8JsonReader;
+                while (utf8JsonReaderOneOf.Read())
                 {
-                    Utf8JsonReader utf8JsonReaderString = utf8JsonReader;
-                    ClientUtils.TryDeserialize<string>(ref utf8JsonReaderString, jsonSerializerOptions, out varString);
+                    if (startingTokenType == JsonTokenType.StartObject && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndObject && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
+                        break;
 
-                    Utf8JsonReader utf8JsonReaderBool = utf8JsonReader;
-                    ClientUtils.TryDeserialize<bool?>(ref utf8JsonReaderBool, jsonSerializerOptions, out varBool);
+                    if (startingTokenType == JsonTokenType.StartArray && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndArray && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
+                        break;
 
-                    Utf8JsonReader utf8JsonReaderInt = utf8JsonReader;
-                    ClientUtils.TryDeserialize<int?>(ref utf8JsonReaderInt, jsonSerializerOptions, out varInt);
+                    if (utf8JsonReaderOneOf.TokenType == JsonTokenType.PropertyName && currentDepth == utf8JsonReaderOneOf.CurrentDepth - 1)
+                    {
+                        Utf8JsonReader utf8JsonReaderString = utf8JsonReader;
+                        ClientUtils.TryDeserialize<string>(ref utf8JsonReaderString, jsonSerializerOptions, out varString);
+
+                        Utf8JsonReader utf8JsonReaderBool = utf8JsonReader;
+                        ClientUtils.TryDeserialize<bool?>(ref utf8JsonReaderBool, jsonSerializerOptions, out varBool);
+
+                        Utf8JsonReader utf8JsonReaderInt = utf8JsonReader;
+                        ClientUtils.TryDeserialize<int?>(ref utf8JsonReaderInt, jsonSerializerOptions, out varInt);
 
-                    Utf8JsonReader utf8JsonReaderDecimal = utf8JsonReader;
-                    ClientUtils.TryDeserialize<decimal?>(ref utf8JsonReaderDecimal, jsonSerializerOptions, out varDecimal);
+                        Utf8JsonReader utf8JsonReaderDecimal = utf8JsonReader;
+                        ClientUtils.TryDeserialize<decimal?>(ref utf8JsonReaderDecimal, jsonSerializerOptions, out varDecimal);
 
-                    Utf8JsonReader utf8JsonReaderMixedSubId = utf8JsonReader;
-                    ClientUtils.TryDeserialize<MixedSubId>(ref utf8JsonReaderMixedSubId, jsonSerializerOptions, out mixedSubId);
+                        Utf8JsonReader utf8JsonReaderMixedSubId = utf8JsonReader;
+                        ClientUtils.TryDeserialize<MixedSubId>(ref utf8JsonReaderMixedSubId, jsonSerializerOptions, out mixedSubId);
+                    }
                 }
             }
 
@@ -250,7 +267,36 @@ public override MixedOneOfContent Read(ref Utf8JsonReader utf8JsonReader, Type t
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, MixedOneOfContent mixedOneOfContent, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (mixedOneOfContent.String != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Int != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Int, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Decimal != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Decimal, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
+            if (mixedOneOfContent.MixedSubId != null)
+            {
+                MixedSubIdJsonConverter mixedSubIdJsonConverter = (MixedSubIdJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(mixedOneOfContent.MixedSubId.GetType()));
+                mixedSubIdJsonConverter.WriteProperties(writer, mixedOneOfContent.MixedSubId, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, mixedOneOfContent, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/NullableShape.cs b/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/NullableShape.cs
index dd205b2df274..4b17a388c158 100644
--- a/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/NullableShape.cs
+++ b/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/NullableShape.cs
@@ -128,9 +128,6 @@ public override NullableShape Read(ref Utf8JsonReader utf8JsonReader, Type typeT
         {
             int currentDepth = utf8JsonReader.CurrentDepth;
 
-            if (utf8JsonReader.TokenType != JsonTokenType.StartObject && utf8JsonReader.TokenType != JsonTokenType.StartArray)
-                throw new JsonException();
-
             JsonTokenType startingTokenType = utf8JsonReader.TokenType;
 
             Option<string> shapeType = default;
diff --git a/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/OneOfString.cs b/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/OneOfString.cs
index af0ceaa278b0..abe2bb642287 100644
--- a/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/OneOfString.cs
+++ b/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/OneOfString.cs
@@ -103,9 +103,6 @@ public override OneOfString Read(ref Utf8JsonReader utf8JsonReader, Type typeToC
         {
             int currentDepth = utf8JsonReader.CurrentDepth;
 
-            if (utf8JsonReader.TokenType != JsonTokenType.StartObject && utf8JsonReader.TokenType != JsonTokenType.StartArray)
-                throw new JsonException();
-
             JsonTokenType startingTokenType = utf8JsonReader.TokenType;
 
             string varString = default;
@@ -146,6 +143,12 @@ public override OneOfString Read(ref Utf8JsonReader utf8JsonReader, Type typeToC
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, OneOfString oneOfString, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (oneOfString.String != null)
+            {
+                JsonSerializer.Serialize(writer, oneOfString.String, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, oneOfString, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/Pig.cs b/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/Pig.cs
index 3d7b78a18292..ec64315fb235 100644
--- a/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/Pig.cs
+++ b/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/Pig.cs
@@ -128,9 +128,6 @@ public override Pig Read(ref Utf8JsonReader utf8JsonReader, Type typeToConvert,
         {
             int currentDepth = utf8JsonReader.CurrentDepth;
 
-            if (utf8JsonReader.TokenType != JsonTokenType.StartObject && utf8JsonReader.TokenType != JsonTokenType.StartArray)
-                throw new JsonException();
-
             JsonTokenType startingTokenType = utf8JsonReader.TokenType;
 
             Option<string> className = default;
diff --git a/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/PolymorphicProperty.cs b/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
index befe6e02ec3a..6e4ff3f20b9c 100644
--- a/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
+++ b/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
@@ -148,9 +148,6 @@ public override PolymorphicProperty Read(ref Utf8JsonReader utf8JsonReader, Type
         {
             int currentDepth = utf8JsonReader.CurrentDepth;
 
-            if (utf8JsonReader.TokenType != JsonTokenType.StartObject && utf8JsonReader.TokenType != JsonTokenType.StartArray)
-                throw new JsonException();
-
             JsonTokenType startingTokenType = utf8JsonReader.TokenType;
 
             bool? varBool = default;
@@ -158,28 +155,45 @@ public override PolymorphicProperty Read(ref Utf8JsonReader utf8JsonReader, Type
             Object varObject = default;
             List<string> list = default;
 
-            Utf8JsonReader utf8JsonReaderOneOf = utf8JsonReader;
-            while (utf8JsonReaderOneOf.Read())
+            if (startingTokenType != JsonTokenType.StartObject && startingTokenType != JsonTokenType.StartArray)
             {
-                if (startingTokenType == JsonTokenType.StartObject && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndObject && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
-                    break;
+                Utf8JsonReader utf8JsonReaderBool = utf8JsonReader;
+                ClientUtils.TryDeserialize<bool?>(ref utf8JsonReaderBool, jsonSerializerOptions, out varBool);
 
-                if (startingTokenType == JsonTokenType.StartArray && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndArray && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
-                    break;
+                Utf8JsonReader utf8JsonReaderString = utf8JsonReader;
+                ClientUtils.TryDeserialize<string>(ref utf8JsonReaderString, jsonSerializerOptions, out varString);
 
-                if (utf8JsonReaderOneOf.TokenType == JsonTokenType.PropertyName && currentDepth == utf8JsonReaderOneOf.CurrentDepth - 1)
+                Utf8JsonReader utf8JsonReaderObject = utf8JsonReader;
+                ClientUtils.TryDeserialize<Object>(ref utf8JsonReaderObject, jsonSerializerOptions, out varObject);
+
+                Utf8JsonReader utf8JsonReaderList = utf8JsonReader;
+                ClientUtils.TryDeserialize<List<string>>(ref utf8JsonReaderList, jsonSerializerOptions, out list);
+            }
+            else
+            {
+                Utf8JsonReader utf8JsonReaderOneOf = utf8JsonReader;
+                while (utf8JsonReaderOneOf.Read())
                 {
-                    Utf8JsonReader utf8JsonReaderBool = utf8JsonReader;
-                    ClientUtils.TryDeserialize<bool?>(ref utf8JsonReaderBool, jsonSerializerOptions, out varBool);
+                    if (startingTokenType == JsonTokenType.StartObject && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndObject && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
+                        break;
 
-                    Utf8JsonReader utf8JsonReaderString = utf8JsonReader;
-                    ClientUtils.TryDeserialize<string>(ref utf8JsonReaderString, jsonSerializerOptions, out varString);
+                    if (startingTokenType == JsonTokenType.StartArray && utf8JsonReaderOneOf.TokenType == JsonTokenType.EndArray && currentDepth == utf8JsonReaderOneOf.CurrentDepth)
+                        break;
 
-                    Utf8JsonReader utf8JsonReaderObject = utf8JsonReader;
-                    ClientUtils.TryDeserialize<Object>(ref utf8JsonReaderObject, jsonSerializerOptions, out varObject);
+                    if (utf8JsonReaderOneOf.TokenType == JsonTokenType.PropertyName && currentDepth == utf8JsonReaderOneOf.CurrentDepth - 1)
+                    {
+                        Utf8JsonReader utf8JsonReaderBool = utf8JsonReader;
+                        ClientUtils.TryDeserialize<bool?>(ref utf8JsonReaderBool, jsonSerializerOptions, out varBool);
+
+                        Utf8JsonReader utf8JsonReaderString = utf8JsonReader;
+                        ClientUtils.TryDeserialize<string>(ref utf8JsonReaderString, jsonSerializerOptions, out varString);
+
+                        Utf8JsonReader utf8JsonReaderObject = utf8JsonReader;
+                        ClientUtils.TryDeserialize<Object>(ref utf8JsonReaderObject, jsonSerializerOptions, out varObject);
 
-                    Utf8JsonReader utf8JsonReaderList = utf8JsonReader;
-                    ClientUtils.TryDeserialize<List<string>>(ref utf8JsonReaderList, jsonSerializerOptions, out list);
+                        Utf8JsonReader utf8JsonReaderList = utf8JsonReader;
+                        ClientUtils.TryDeserialize<List<string>>(ref utf8JsonReaderList, jsonSerializerOptions, out list);
+                    }
                 }
             }
 
@@ -228,6 +242,30 @@ public override PolymorphicProperty Read(ref Utf8JsonReader utf8JsonReader, Type
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, PolymorphicProperty polymorphicProperty, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (polymorphicProperty.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.String != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.Object != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Object, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.List != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.List, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, polymorphicProperty, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/Quadrilateral.cs b/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/Quadrilateral.cs
index f1b8095c949f..2381d0df3f1e 100644
--- a/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/Quadrilateral.cs
+++ b/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/Quadrilateral.cs
@@ -128,9 +128,6 @@ public override Quadrilateral Read(ref Utf8JsonReader utf8JsonReader, Type typeT
         {
             int currentDepth = utf8JsonReader.CurrentDepth;
 
-            if (utf8JsonReader.TokenType != JsonTokenType.StartObject && utf8JsonReader.TokenType != JsonTokenType.StartArray)
-                throw new JsonException();
-
             JsonTokenType startingTokenType = utf8JsonReader.TokenType;
 
             Option<string> quadrilateralType = default;
diff --git a/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/Shape.cs b/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/Shape.cs
index 7a2dd62962fb..d230cf0bb29c 100644
--- a/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/Shape.cs
+++ b/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/Shape.cs
@@ -128,9 +128,6 @@ public override Shape Read(ref Utf8JsonReader utf8JsonReader, Type typeToConvert
         {
             int currentDepth = utf8JsonReader.CurrentDepth;
 
-            if (utf8JsonReader.TokenType != JsonTokenType.StartObject && utf8JsonReader.TokenType != JsonTokenType.StartArray)
-                throw new JsonException();
-
             JsonTokenType startingTokenType = utf8JsonReader.TokenType;
 
             Option<string> shapeType = default;
diff --git a/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/ShapeOrNull.cs b/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/ShapeOrNull.cs
index 52a892aeb9e1..30d965bad4c6 100644
--- a/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/ShapeOrNull.cs
+++ b/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/ShapeOrNull.cs
@@ -128,9 +128,6 @@ public override ShapeOrNull Read(ref Utf8JsonReader utf8JsonReader, Type typeToC
         {
             int currentDepth = utf8JsonReader.CurrentDepth;
 
-            if (utf8JsonReader.TokenType != JsonTokenType.StartObject && utf8JsonReader.TokenType != JsonTokenType.StartArray)
-                throw new JsonException();
-
             JsonTokenType startingTokenType = utf8JsonReader.TokenType;
 
             Option<string> shapeType = default;
diff --git a/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/Triangle.cs b/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/Triangle.cs
index 9e1ae42200c6..96859dae2927 100644
--- a/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/Triangle.cs
+++ b/samples/client/petstore/csharp/generichost/net9/FormModels/src/Org.OpenAPITools/Model/Triangle.cs
@@ -143,9 +143,6 @@ public override Triangle Read(ref Utf8JsonReader utf8JsonReader, Type typeToConv
         {
             int currentDepth = utf8JsonReader.CurrentDepth;
 
-            if (utf8JsonReader.TokenType != JsonTokenType.StartObject && utf8JsonReader.TokenType != JsonTokenType.StartArray)
-                throw new JsonException();
-
             JsonTokenType startingTokenType = utf8JsonReader.TokenType;
 
             Option<string> triangleType = default;
diff --git a/samples/client/petstore/csharp/generichost/net9/NullReferenceTypes/src/Org.OpenAPITools/Model/Fruit.cs b/samples/client/petstore/csharp/generichost/net9/NullReferenceTypes/src/Org.OpenAPITools/Model/Fruit.cs
index ec0062ba20d3..67cb3b13af6c 100644
--- a/samples/client/petstore/csharp/generichost/net9/NullReferenceTypes/src/Org.OpenAPITools/Model/Fruit.cs
+++ b/samples/client/petstore/csharp/generichost/net9/NullReferenceTypes/src/Org.OpenAPITools/Model/Fruit.cs
@@ -206,6 +206,17 @@ public override Fruit Read(ref Utf8JsonReader utf8JsonReader, Type typeToConvert
         public override void Write(Utf8JsonWriter writer, Fruit fruit, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruit.Apple != null)
+            {
+                AppleJsonConverter appleJsonConverter = (AppleJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Apple.GetType()));
+                appleJsonConverter.WriteProperties(writer, fruit.Apple, jsonSerializerOptions);
+            }
+
+            if (fruit.Banana != null)
+            {
+                BananaJsonConverter bananaJsonConverter = (BananaJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Banana.GetType()));
+                bananaJsonConverter.WriteProperties(writer, fruit.Banana, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruit, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net9/NullReferenceTypes/src/Org.OpenAPITools/Model/FruitReq.cs b/samples/client/petstore/csharp/generichost/net9/NullReferenceTypes/src/Org.OpenAPITools/Model/FruitReq.cs
index af1802aab1a9..d73d15fdc718 100644
--- a/samples/client/petstore/csharp/generichost/net9/NullReferenceTypes/src/Org.OpenAPITools/Model/FruitReq.cs
+++ b/samples/client/petstore/csharp/generichost/net9/NullReferenceTypes/src/Org.OpenAPITools/Model/FruitReq.cs
@@ -180,6 +180,17 @@ public override FruitReq Read(ref Utf8JsonReader utf8JsonReader, Type typeToConv
         public override void Write(Utf8JsonWriter writer, FruitReq fruitReq, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruitReq.AppleReq != null)
+            {
+                AppleReqJsonConverter appleReqJsonConverter = (AppleReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.AppleReq.GetType()));
+                appleReqJsonConverter.WriteProperties(writer, fruitReq.AppleReq, jsonSerializerOptions);
+            }
+
+            if (fruitReq.BananaReq != null)
+            {
+                BananaReqJsonConverter bananaReqJsonConverter = (BananaReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.BananaReq.GetType()));
+                bananaReqJsonConverter.WriteProperties(writer, fruitReq.BananaReq, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruitReq, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net9/NullReferenceTypes/src/Org.OpenAPITools/Model/MixedOneOfContent.cs b/samples/client/petstore/csharp/generichost/net9/NullReferenceTypes/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
index bac36e3cbe70..2b27c5610dad 100644
--- a/samples/client/petstore/csharp/generichost/net9/NullReferenceTypes/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
+++ b/samples/client/petstore/csharp/generichost/net9/NullReferenceTypes/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
@@ -252,7 +252,36 @@ public override MixedOneOfContent Read(ref Utf8JsonReader utf8JsonReader, Type t
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, MixedOneOfContent mixedOneOfContent, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (mixedOneOfContent.String != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Int != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Int, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Decimal != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Decimal, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
+            if (mixedOneOfContent.MixedSubId != null)
+            {
+                MixedSubIdJsonConverter mixedSubIdJsonConverter = (MixedSubIdJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(mixedOneOfContent.MixedSubId.GetType()));
+                mixedSubIdJsonConverter.WriteProperties(writer, mixedOneOfContent.MixedSubId, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, mixedOneOfContent, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net9/NullReferenceTypes/src/Org.OpenAPITools/Model/OneOfString.cs b/samples/client/petstore/csharp/generichost/net9/NullReferenceTypes/src/Org.OpenAPITools/Model/OneOfString.cs
index e03117058c32..50b6a7869b9f 100644
--- a/samples/client/petstore/csharp/generichost/net9/NullReferenceTypes/src/Org.OpenAPITools/Model/OneOfString.cs
+++ b/samples/client/petstore/csharp/generichost/net9/NullReferenceTypes/src/Org.OpenAPITools/Model/OneOfString.cs
@@ -148,6 +148,12 @@ public override OneOfString Read(ref Utf8JsonReader utf8JsonReader, Type typeToC
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, OneOfString oneOfString, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (oneOfString.String != null)
+            {
+                JsonSerializer.Serialize(writer, oneOfString.String, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, oneOfString, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/net9/NullReferenceTypes/src/Org.OpenAPITools/Model/PolymorphicProperty.cs b/samples/client/petstore/csharp/generichost/net9/NullReferenceTypes/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
index d33ed7654562..6aeb2e63b84d 100644
--- a/samples/client/petstore/csharp/generichost/net9/NullReferenceTypes/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
+++ b/samples/client/petstore/csharp/generichost/net9/NullReferenceTypes/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
@@ -230,6 +230,30 @@ public override PolymorphicProperty Read(ref Utf8JsonReader utf8JsonReader, Type
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, PolymorphicProperty polymorphicProperty, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (polymorphicProperty.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.String != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.Object != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Object, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.List != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.List, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, polymorphicProperty, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/net9/OneOf/src/Org.OpenAPITools/Model/Fruit.cs b/samples/client/petstore/csharp/generichost/net9/OneOf/src/Org.OpenAPITools/Model/Fruit.cs
index 1a4743015087..be03ed7e708e 100644
--- a/samples/client/petstore/csharp/generichost/net9/OneOf/src/Org.OpenAPITools/Model/Fruit.cs
+++ b/samples/client/petstore/csharp/generichost/net9/OneOf/src/Org.OpenAPITools/Model/Fruit.cs
@@ -237,6 +237,23 @@ public override Fruit Read(ref Utf8JsonReader utf8JsonReader, Type typeToConvert
         public override void Write(Utf8JsonWriter writer, Fruit fruit, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruit.Apple != null)
+            {
+                AppleJsonConverter appleJsonConverter = (AppleJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Apple.GetType()));
+                appleJsonConverter.WriteProperties(writer, fruit.Apple, jsonSerializerOptions);
+            }
+
+            if (fruit.Banana != null)
+            {
+                BananaJsonConverter bananaJsonConverter = (BananaJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Banana.GetType()));
+                bananaJsonConverter.WriteProperties(writer, fruit.Banana, jsonSerializerOptions);
+            }
+
+            if (fruit.Orange != null)
+            {
+                OrangeJsonConverter orangeJsonConverter = (OrangeJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Orange.GetType()));
+                orangeJsonConverter.WriteProperties(writer, fruit.Orange, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruit, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net9/Petstore/src/Org.OpenAPITools/Model/Fruit.cs b/samples/client/petstore/csharp/generichost/net9/Petstore/src/Org.OpenAPITools/Model/Fruit.cs
index ca703d27f96c..523e4981cf08 100644
--- a/samples/client/petstore/csharp/generichost/net9/Petstore/src/Org.OpenAPITools/Model/Fruit.cs
+++ b/samples/client/petstore/csharp/generichost/net9/Petstore/src/Org.OpenAPITools/Model/Fruit.cs
@@ -204,6 +204,17 @@ public override Fruit Read(ref Utf8JsonReader utf8JsonReader, Type typeToConvert
         public override void Write(Utf8JsonWriter writer, Fruit fruit, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruit.Apple != null)
+            {
+                AppleJsonConverter appleJsonConverter = (AppleJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Apple.GetType()));
+                appleJsonConverter.WriteProperties(writer, fruit.Apple, jsonSerializerOptions);
+            }
+
+            if (fruit.Banana != null)
+            {
+                BananaJsonConverter bananaJsonConverter = (BananaJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Banana.GetType()));
+                bananaJsonConverter.WriteProperties(writer, fruit.Banana, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruit, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net9/Petstore/src/Org.OpenAPITools/Model/FruitReq.cs b/samples/client/petstore/csharp/generichost/net9/Petstore/src/Org.OpenAPITools/Model/FruitReq.cs
index 440fbefb11ac..ac498f51caf9 100644
--- a/samples/client/petstore/csharp/generichost/net9/Petstore/src/Org.OpenAPITools/Model/FruitReq.cs
+++ b/samples/client/petstore/csharp/generichost/net9/Petstore/src/Org.OpenAPITools/Model/FruitReq.cs
@@ -178,6 +178,17 @@ public override FruitReq Read(ref Utf8JsonReader utf8JsonReader, Type typeToConv
         public override void Write(Utf8JsonWriter writer, FruitReq fruitReq, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruitReq.AppleReq != null)
+            {
+                AppleReqJsonConverter appleReqJsonConverter = (AppleReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.AppleReq.GetType()));
+                appleReqJsonConverter.WriteProperties(writer, fruitReq.AppleReq, jsonSerializerOptions);
+            }
+
+            if (fruitReq.BananaReq != null)
+            {
+                BananaReqJsonConverter bananaReqJsonConverter = (BananaReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.BananaReq.GetType()));
+                bananaReqJsonConverter.WriteProperties(writer, fruitReq.BananaReq, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruitReq, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net9/Petstore/src/Org.OpenAPITools/Model/MixedOneOfContent.cs b/samples/client/petstore/csharp/generichost/net9/Petstore/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
index 88d0a9a352de..270d653642cd 100644
--- a/samples/client/petstore/csharp/generichost/net9/Petstore/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
+++ b/samples/client/petstore/csharp/generichost/net9/Petstore/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
@@ -250,7 +250,36 @@ public override MixedOneOfContent Read(ref Utf8JsonReader utf8JsonReader, Type t
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, MixedOneOfContent mixedOneOfContent, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (mixedOneOfContent.String != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Int != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Int, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Decimal != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Decimal, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
+            if (mixedOneOfContent.MixedSubId != null)
+            {
+                MixedSubIdJsonConverter mixedSubIdJsonConverter = (MixedSubIdJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(mixedOneOfContent.MixedSubId.GetType()));
+                mixedSubIdJsonConverter.WriteProperties(writer, mixedOneOfContent.MixedSubId, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, mixedOneOfContent, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net9/Petstore/src/Org.OpenAPITools/Model/OneOfString.cs b/samples/client/petstore/csharp/generichost/net9/Petstore/src/Org.OpenAPITools/Model/OneOfString.cs
index af0ceaa278b0..b5b0a324b1eb 100644
--- a/samples/client/petstore/csharp/generichost/net9/Petstore/src/Org.OpenAPITools/Model/OneOfString.cs
+++ b/samples/client/petstore/csharp/generichost/net9/Petstore/src/Org.OpenAPITools/Model/OneOfString.cs
@@ -146,6 +146,12 @@ public override OneOfString Read(ref Utf8JsonReader utf8JsonReader, Type typeToC
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, OneOfString oneOfString, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (oneOfString.String != null)
+            {
+                JsonSerializer.Serialize(writer, oneOfString.String, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, oneOfString, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/net9/Petstore/src/Org.OpenAPITools/Model/PolymorphicProperty.cs b/samples/client/petstore/csharp/generichost/net9/Petstore/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
index befe6e02ec3a..c7ef5eda6387 100644
--- a/samples/client/petstore/csharp/generichost/net9/Petstore/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
+++ b/samples/client/petstore/csharp/generichost/net9/Petstore/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
@@ -228,6 +228,30 @@ public override PolymorphicProperty Read(ref Utf8JsonReader utf8JsonReader, Type
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, PolymorphicProperty polymorphicProperty, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (polymorphicProperty.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.String != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.Object != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Object, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.List != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.List, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, polymorphicProperty, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/net9/SourceGeneration/src/Org.OpenAPITools/Model/Fruit.cs b/samples/client/petstore/csharp/generichost/net9/SourceGeneration/src/Org.OpenAPITools/Model/Fruit.cs
index 9bad6c70417c..8e385da82a91 100644
--- a/samples/client/petstore/csharp/generichost/net9/SourceGeneration/src/Org.OpenAPITools/Model/Fruit.cs
+++ b/samples/client/petstore/csharp/generichost/net9/SourceGeneration/src/Org.OpenAPITools/Model/Fruit.cs
@@ -207,6 +207,17 @@ public override Fruit Read(ref Utf8JsonReader utf8JsonReader, Type typeToConvert
         public override void Write(Utf8JsonWriter writer, Fruit fruit, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruit.Apple != null)
+            {
+                AppleJsonConverter appleJsonConverter = (AppleJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Apple.GetType()));
+                appleJsonConverter.WriteProperties(writer, fruit.Apple, jsonSerializerOptions);
+            }
+
+            if (fruit.Banana != null)
+            {
+                BananaJsonConverter bananaJsonConverter = (BananaJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Banana.GetType()));
+                bananaJsonConverter.WriteProperties(writer, fruit.Banana, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruit, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net9/SourceGeneration/src/Org.OpenAPITools/Model/FruitReq.cs b/samples/client/petstore/csharp/generichost/net9/SourceGeneration/src/Org.OpenAPITools/Model/FruitReq.cs
index ed5e1e35c028..361da9371288 100644
--- a/samples/client/petstore/csharp/generichost/net9/SourceGeneration/src/Org.OpenAPITools/Model/FruitReq.cs
+++ b/samples/client/petstore/csharp/generichost/net9/SourceGeneration/src/Org.OpenAPITools/Model/FruitReq.cs
@@ -181,6 +181,17 @@ public override FruitReq Read(ref Utf8JsonReader utf8JsonReader, Type typeToConv
         public override void Write(Utf8JsonWriter writer, FruitReq fruitReq, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruitReq.AppleReq != null)
+            {
+                AppleReqJsonConverter appleReqJsonConverter = (AppleReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.AppleReq.GetType()));
+                appleReqJsonConverter.WriteProperties(writer, fruitReq.AppleReq, jsonSerializerOptions);
+            }
+
+            if (fruitReq.BananaReq != null)
+            {
+                BananaReqJsonConverter bananaReqJsonConverter = (BananaReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.BananaReq.GetType()));
+                bananaReqJsonConverter.WriteProperties(writer, fruitReq.BananaReq, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruitReq, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net9/SourceGeneration/src/Org.OpenAPITools/Model/MixedOneOfContent.cs b/samples/client/petstore/csharp/generichost/net9/SourceGeneration/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
index ca6ca27187dd..c96886067b6b 100644
--- a/samples/client/petstore/csharp/generichost/net9/SourceGeneration/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
+++ b/samples/client/petstore/csharp/generichost/net9/SourceGeneration/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
@@ -253,7 +253,36 @@ public override MixedOneOfContent Read(ref Utf8JsonReader utf8JsonReader, Type t
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, MixedOneOfContent mixedOneOfContent, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (mixedOneOfContent.String != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Int != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Int, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Decimal != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Decimal, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
+            if (mixedOneOfContent.MixedSubId != null)
+            {
+                MixedSubIdJsonConverter mixedSubIdJsonConverter = (MixedSubIdJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(mixedOneOfContent.MixedSubId.GetType()));
+                mixedSubIdJsonConverter.WriteProperties(writer, mixedOneOfContent.MixedSubId, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, mixedOneOfContent, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/net9/SourceGeneration/src/Org.OpenAPITools/Model/OneOfString.cs b/samples/client/petstore/csharp/generichost/net9/SourceGeneration/src/Org.OpenAPITools/Model/OneOfString.cs
index 4a46f52ead3a..df1341c55fed 100644
--- a/samples/client/petstore/csharp/generichost/net9/SourceGeneration/src/Org.OpenAPITools/Model/OneOfString.cs
+++ b/samples/client/petstore/csharp/generichost/net9/SourceGeneration/src/Org.OpenAPITools/Model/OneOfString.cs
@@ -149,6 +149,12 @@ public override OneOfString Read(ref Utf8JsonReader utf8JsonReader, Type typeToC
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, OneOfString oneOfString, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (oneOfString.String != null)
+            {
+                JsonSerializer.Serialize(writer, oneOfString.String, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, oneOfString, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/net9/SourceGeneration/src/Org.OpenAPITools/Model/PolymorphicProperty.cs b/samples/client/petstore/csharp/generichost/net9/SourceGeneration/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
index d3e959b95a67..114391721fd3 100644
--- a/samples/client/petstore/csharp/generichost/net9/SourceGeneration/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
+++ b/samples/client/petstore/csharp/generichost/net9/SourceGeneration/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
@@ -231,6 +231,30 @@ public override PolymorphicProperty Read(ref Utf8JsonReader utf8JsonReader, Type
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, PolymorphicProperty polymorphicProperty, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (polymorphicProperty.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.String != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.Object != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Object, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.List != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.List, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, polymorphicProperty, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/standard2.0/Petstore/src/Org.OpenAPITools/Model/Fruit.cs b/samples/client/petstore/csharp/generichost/standard2.0/Petstore/src/Org.OpenAPITools/Model/Fruit.cs
index ba5d85932b34..453be949b65f 100644
--- a/samples/client/petstore/csharp/generichost/standard2.0/Petstore/src/Org.OpenAPITools/Model/Fruit.cs
+++ b/samples/client/petstore/csharp/generichost/standard2.0/Petstore/src/Org.OpenAPITools/Model/Fruit.cs
@@ -204,6 +204,17 @@ public override Fruit Read(ref Utf8JsonReader utf8JsonReader, Type typeToConvert
         public override void Write(Utf8JsonWriter writer, Fruit fruit, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruit.Apple != null)
+            {
+                AppleJsonConverter appleJsonConverter = (AppleJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Apple.GetType()));
+                appleJsonConverter.WriteProperties(writer, fruit.Apple, jsonSerializerOptions);
+            }
+
+            if (fruit.Banana != null)
+            {
+                BananaJsonConverter bananaJsonConverter = (BananaJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruit.Banana.GetType()));
+                bananaJsonConverter.WriteProperties(writer, fruit.Banana, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruit, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/standard2.0/Petstore/src/Org.OpenAPITools/Model/FruitReq.cs b/samples/client/petstore/csharp/generichost/standard2.0/Petstore/src/Org.OpenAPITools/Model/FruitReq.cs
index 440fbefb11ac..ac498f51caf9 100644
--- a/samples/client/petstore/csharp/generichost/standard2.0/Petstore/src/Org.OpenAPITools/Model/FruitReq.cs
+++ b/samples/client/petstore/csharp/generichost/standard2.0/Petstore/src/Org.OpenAPITools/Model/FruitReq.cs
@@ -178,6 +178,17 @@ public override FruitReq Read(ref Utf8JsonReader utf8JsonReader, Type typeToConv
         public override void Write(Utf8JsonWriter writer, FruitReq fruitReq, JsonSerializerOptions jsonSerializerOptions)
         {
             writer.WriteStartObject();
+            if (fruitReq.AppleReq != null)
+            {
+                AppleReqJsonConverter appleReqJsonConverter = (AppleReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.AppleReq.GetType()));
+                appleReqJsonConverter.WriteProperties(writer, fruitReq.AppleReq, jsonSerializerOptions);
+            }
+
+            if (fruitReq.BananaReq != null)
+            {
+                BananaReqJsonConverter bananaReqJsonConverter = (BananaReqJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(fruitReq.BananaReq.GetType()));
+                bananaReqJsonConverter.WriteProperties(writer, fruitReq.BananaReq, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, fruitReq, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/standard2.0/Petstore/src/Org.OpenAPITools/Model/MixedOneOfContent.cs b/samples/client/petstore/csharp/generichost/standard2.0/Petstore/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
index 88d0a9a352de..270d653642cd 100644
--- a/samples/client/petstore/csharp/generichost/standard2.0/Petstore/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
+++ b/samples/client/petstore/csharp/generichost/standard2.0/Petstore/src/Org.OpenAPITools/Model/MixedOneOfContent.cs
@@ -250,7 +250,36 @@ public override MixedOneOfContent Read(ref Utf8JsonReader utf8JsonReader, Type t
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, MixedOneOfContent mixedOneOfContent, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (mixedOneOfContent.String != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Int != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Int, jsonSerializerOptions);
+                return;
+            }
+
+            if (mixedOneOfContent.Decimal != null)
+            {
+                JsonSerializer.Serialize(writer, mixedOneOfContent.Decimal, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
+            if (mixedOneOfContent.MixedSubId != null)
+            {
+                MixedSubIdJsonConverter mixedSubIdJsonConverter = (MixedSubIdJsonConverter) jsonSerializerOptions.Converters.First(c => c.CanConvert(mixedOneOfContent.MixedSubId.GetType()));
+                mixedSubIdJsonConverter.WriteProperties(writer, mixedOneOfContent.MixedSubId, jsonSerializerOptions);
+            }
 
             WriteProperties(writer, mixedOneOfContent, jsonSerializerOptions);
             writer.WriteEndObject();
diff --git a/samples/client/petstore/csharp/generichost/standard2.0/Petstore/src/Org.OpenAPITools/Model/OneOfString.cs b/samples/client/petstore/csharp/generichost/standard2.0/Petstore/src/Org.OpenAPITools/Model/OneOfString.cs
index af0ceaa278b0..b5b0a324b1eb 100644
--- a/samples/client/petstore/csharp/generichost/standard2.0/Petstore/src/Org.OpenAPITools/Model/OneOfString.cs
+++ b/samples/client/petstore/csharp/generichost/standard2.0/Petstore/src/Org.OpenAPITools/Model/OneOfString.cs
@@ -146,6 +146,12 @@ public override OneOfString Read(ref Utf8JsonReader utf8JsonReader, Type typeToC
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, OneOfString oneOfString, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (oneOfString.String != null)
+            {
+                JsonSerializer.Serialize(writer, oneOfString.String, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, oneOfString, jsonSerializerOptions);
diff --git a/samples/client/petstore/csharp/generichost/standard2.0/Petstore/src/Org.OpenAPITools/Model/PolymorphicProperty.cs b/samples/client/petstore/csharp/generichost/standard2.0/Petstore/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
index befe6e02ec3a..c7ef5eda6387 100644
--- a/samples/client/petstore/csharp/generichost/standard2.0/Petstore/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
+++ b/samples/client/petstore/csharp/generichost/standard2.0/Petstore/src/Org.OpenAPITools/Model/PolymorphicProperty.cs
@@ -228,6 +228,30 @@ public override PolymorphicProperty Read(ref Utf8JsonReader utf8JsonReader, Type
         /// <exception cref="NotImplementedException"></exception>
         public override void Write(Utf8JsonWriter writer, PolymorphicProperty polymorphicProperty, JsonSerializerOptions jsonSerializerOptions)
         {
+            if (polymorphicProperty.Bool != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Bool, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.String != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.String, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.Object != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.Object, jsonSerializerOptions);
+                return;
+            }
+
+            if (polymorphicProperty.List != null)
+            {
+                JsonSerializer.Serialize(writer, polymorphicProperty.List, jsonSerializerOptions);
+                return;
+            }
+
             writer.WriteStartObject();
 
             WriteProperties(writer, polymorphicProperty, jsonSerializerOptions);