OpenAPITools · wing328 · Dec 22, 2025 · Dec 21, 2025 · Dec 21, 2025 · Dec 21, 2025
diff --git a/.github/workflows/samples-dotnet-fx.yaml b/.github/workflows/samples-dotnet-fx.yaml
@@ -11,7 +11,7 @@ on:
       - samples/client/petstore/csharp/generichost/net4.8/**
 jobs:
   build:
-    name: Build .Net projects
+    name: Build .Net Framework projects
     runs-on: windows-latest
     strategy:
       fail-fast: false

diff --git a/.github/workflows/samples-dotnet-standard.yaml b/.github/workflows/samples-dotnet-standard.yaml
@@ -15,7 +15,7 @@ on:
       - samples/client/petstore/csharp/unityWebRequest/standard2.0/**
 jobs:
   build:
-    name: Build .Net projects
+    name: Build .Net Standard projects
     runs-on: windows-latest
     strategy:
       fail-fast: false

diff --git a/.github/workflows/samples-dotnet10.yaml b/.github/workflows/samples-dotnet10.yaml
@@ -0,0 +1,59 @@
+name: Samples C# .Net 10 Clients
+
+on:
+  push:
+    paths:
+      - samples/client/petstore/csharp/generichost/latest/**
+      - samples/client/petstore/csharp/generichost/net10/**
+      - samples/client/petstore/csharp/httpclient/net10/**
+      - samples/client/petstore/csharp/restsharp/net10/**
+      - samples/client/petstore/csharp/unityWebRequest/net10/**
+  pull_request:
+    paths:
+      - samples/client/petstore/csharp/generichost/latest/**
+      - samples/client/petstore/csharp/generichost/net10/**
+      - samples/client/petstore/csharp/httpclient/net10/**
+      - samples/client/petstore/csharp/restsharp/net10/**
+      - samples/client/petstore/csharp/unityWebRequest/net10/**
+jobs:
+  build:
+    name: Build .Net 10 projects
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        sample:
+          - samples/client/petstore/csharp/generichost/latest/ComposedEnum
+          - samples/client/petstore/csharp/generichost/latest/InlineEnumAnyOf
+          - samples/client/petstore/csharp/generichost/latest/Tags
+          - samples/client/petstore/csharp/generichost/latest/HelloWorld
+          - samples/client/petstore/csharp/generichost/latest/OneOfList
+          - samples/client/petstore/csharp/generichost/net10/AllOf
+          - samples/client/petstore/csharp/generichost/net10/AnyOf
+          - samples/client/petstore/csharp/generichost/net10/AnyOfNoCompare
+          - samples/client/petstore/csharp/generichost/net10/FormModels
+          # - samples/client/petstore/csharp/generichost/net10/ManualPetstoreTests
+          # - samples/client/petstore/csharp/generichost/net10/ManualSourceGenerationTests
+          - samples/client/petstore/csharp/generichost/net10/NullReferenceTypes
+          - samples/client/petstore/csharp/generichost/net10/OneOf
+          - samples/client/petstore/csharp/generichost/net10/Petstore
+          - samples/client/petstore/csharp/generichost/net10/SourceGeneration
+          - samples/client/petstore/csharp/generichost/net10/UseDateTimeForDate
+          # restsharp
+          - samples/client/petstore/csharp/restsharp/net10/EnumMappings
+          # httpclient
+          - samples/client/petstore/csharp/httpclient/net10/Petstore
+          - samples/client/petstore/csharp/httpclient/net10/Petstore-nonPublicApi
+          # unity
+          # - samples/client/petstore/csharp/unityWebRequest/net10/Petstore
+    steps:
+      - uses: actions/checkout@v5
+      - uses: actions/setup-dotnet@v5.0.0
+        with:
+          dotnet-version: '10.x'
+      - name: Build
+        working-directory: ${{ matrix.sample }}
+        run: dotnet build Org.OpenAPITools.sln
+      - name: Test
+        working-directory: ${{ matrix.sample }}
+        run: dotnet test Org.OpenAPITools.sln
diff --git a/.github/workflows/samples-dotnet8.yaml b/.github/workflows/samples-dotnet8.yaml
@@ -15,7 +15,7 @@ on:
       - samples/client/petstore/csharp/unityWebRequest/net8/**
 jobs:
   build:
-    name: Build .Net projects
+    name: Build .Net 8 projects
     runs-on: ubuntu-latest
     strategy:
       fail-fast: false

diff --git a/.github/workflows/samples-dotnet9.yaml b/.github/workflows/samples-dotnet9.yaml
@@ -3,31 +3,24 @@ name: Samples C# .Net 9 Clients
 on:
   push:
     paths:
-      - samples/client/petstore/csharp/generichost/latest/**
       - samples/client/petstore/csharp/generichost/net9/**
       - samples/client/petstore/csharp/httpclient/net9/**
       - samples/client/petstore/csharp/restsharp/net9/**
       - samples/client/petstore/csharp/unityWebRequest/net9/**
   pull_request:
     paths:
-      - samples/client/petstore/csharp/generichost/latest/**
       - samples/client/petstore/csharp/generichost/net9/**
       - samples/client/petstore/csharp/httpclient/net9/**
       - samples/client/petstore/csharp/restsharp/net9/**
       - samples/client/petstore/csharp/unityWebRequest/net9/**
 jobs:
   build:
-    name: Build .Net projects
+    name: Build .Net 9 projects
     runs-on: ubuntu-latest
     strategy:
       fail-fast: false
       matrix:
         sample:
-          - samples/client/petstore/csharp/generichost/latest/ComposedEnum
-          - samples/client/petstore/csharp/generichost/latest/InlineEnumAnyOf
-          - samples/client/petstore/csharp/generichost/latest/Tags
-          - samples/client/petstore/csharp/generichost/latest/HelloWorld
-          - samples/client/petstore/csharp/generichost/latest/OneOfList
           - samples/client/petstore/csharp/generichost/net9/AllOf
           - samples/client/petstore/csharp/generichost/net9/AnyOf
           - samples/client/petstore/csharp/generichost/net9/AnyOfNoCompare

diff --git a/bin/configs/csharp-generichost-net10-allOf.yaml b/bin/configs/csharp-generichost-net10-allOf.yaml
@@ -0,0 +1,14 @@
+# for csharp generichost
+generatorName: csharp
+outputDir: samples/client/petstore/csharp/generichost/net10/AllOf
+inputSpec: modules/openapi-generator/src/test/resources/3_0/allOf.yaml
+templateDir: modules/openapi-generator/src/main/resources/csharp
+additionalProperties:
+  packageGuid: '{321C8C3F-0156-40C1-AE42-D59761FB9B6C}'
+  useCompareNetObjects: true 
+  disallowAdditionalPropertiesIfNotPresent: false
+  nullableReferenceTypes: true
+  equatable: true
+  targetFramework: net10.0
+  modelPropertySorting: alphabetical
+  operationParameterSorting: alphabetical
diff --git a/bin/configs/csharp-generichost-net10-anyOf.yaml b/bin/configs/csharp-generichost-net10-anyOf.yaml
@@ -0,0 +1,14 @@
+# for csharp generichost
+generatorName: csharp
+outputDir: samples/client/petstore/csharp/generichost/net10/AnyOf
+inputSpec: modules/openapi-generator/src/test/resources/3_0/anyOf.yaml
+templateDir: modules/openapi-generator/src/main/resources/csharp
+additionalProperties:
+  packageGuid: '{321C8C3F-0156-40C1-AE42-D59761FB9B6C}'
+  useCompareNetObjects: true 
+  disallowAdditionalPropertiesIfNotPresent: false
+  nullableReferenceTypes: true
+  equatable: true
+  targetFramework: net10.0
+  modelPropertySorting: alphabetical
+  operationParameterSorting: alphabetical
diff --git a/bin/configs/csharp-generichost-net10-anyOfNoCompare.yaml b/bin/configs/csharp-generichost-net10-anyOfNoCompare.yaml
@@ -0,0 +1,14 @@
+# for csharp generichost
+generatorName: csharp
+outputDir: samples/client/petstore/csharp/generichost/net10/AnyOfNoCompare
+inputSpec: modules/openapi-generator/src/test/resources/3_0/anyOf.yaml
+templateDir: modules/openapi-generator/src/main/resources/csharp
+additionalProperties:
+  packageGuid: '{321C8C3F-0156-40C1-AE42-D59761FB9B6C}'
+  useCompareNetObjects: false
+  disallowAdditionalPropertiesIfNotPresent: false
+  nullableReferenceTypes: true
+  equatable: true
+  targetFramework: net10.0
+  modelPropertySorting: alphabetical
+  operationParameterSorting: alphabetical
diff --git a/bin/configs/csharp-generichost-net10-formModels.yaml b/bin/configs/csharp-generichost-net10-formModels.yaml
@@ -0,0 +1,17 @@
+# for csharp generichost
+generatorName: csharp
+outputDir: samples/client/petstore/csharp/generichost/net10/FormModels
+inputSpec: modules/openapi-generator/src/test/resources/3_0/csharp/petstore-with-fake-endpoints-models-for-testing-with-http-signature.yaml
+templateDir: modules/openapi-generator/src/main/resources/csharp
+additionalProperties:
+  packageGuid: '{321C8C3F-0156-40C1-AE42-D59761FB9B6C}'
+  useCompareNetObjects: true 
+  disallowAdditionalPropertiesIfNotPresent: false
+  nullableReferenceTypes: false
+  equatable: true
+  targetFramework: net10.0
+  skipFormModel: false
+  modelPropertySorting: alphabetical
+  operationParameterSorting: alphabetical
+inlineSchemaOptions:
+  RESOLVE_INLINE_ENUMS: true
diff --git a/bin/configs/csharp-generichost-net10-nrt-useSourceGeneration.yaml b/bin/configs/csharp-generichost-net10-nrt-useSourceGeneration.yaml
@@ -0,0 +1,14 @@
+# for csharp generichost
+generatorName: csharp
+outputDir: samples/client/petstore/csharp/generichost/net10/SourceGeneration
+inputSpec: modules/openapi-generator/src/test/resources/3_0/csharp/petstore-with-fake-endpoints-models-for-testing-with-http-signature.yaml
+templateDir: modules/openapi-generator/src/main/resources/csharp
+additionalProperties:
+  packageGuid: '{321C8C3F-0156-40C1-AE42-D59761FB9B6C}'
+  useCompareNetObjects: true 
+  disallowAdditionalPropertiesIfNotPresent: false
+  useSourceGeneration: true
+  equatable: true
+  targetFramework: net10.0
+  modelPropertySorting: alphabetical
+  operationParameterSorting: alphabetical
diff --git a/bin/configs/csharp-generichost-net10-nrt.yaml b/bin/configs/csharp-generichost-net10-nrt.yaml
@@ -0,0 +1,14 @@
+# for csharp generichost
+generatorName: csharp
+outputDir: samples/client/petstore/csharp/generichost/net10/NullReferenceTypes
+inputSpec: modules/openapi-generator/src/test/resources/3_0/csharp/petstore-with-fake-endpoints-models-for-testing-with-http-signature.yaml
+templateDir: modules/openapi-generator/src/main/resources/csharp
+additionalProperties:
+  packageGuid: '{321C8C3F-0156-40C1-AE42-D59761FB9B6C}'
+  useCompareNetObjects: true 
+  disallowAdditionalPropertiesIfNotPresent: false
+  nullableReferenceTypes: true
+  equatable: true
+  targetFramework: net10.0
+  modelPropertySorting: alphabetical
+  operationParameterSorting: alphabetical
diff --git a/bin/configs/csharp-generichost-net10-oneOf.yaml b/bin/configs/csharp-generichost-net10-oneOf.yaml
@@ -0,0 +1,14 @@
+# for csharp generichost
+generatorName: csharp
+outputDir: samples/client/petstore/csharp/generichost/net10/OneOf
+inputSpec: modules/openapi-generator/src/test/resources/3_0/oneOf.yaml
+templateDir: modules/openapi-generator/src/main/resources/csharp
+additionalProperties:
+  packageGuid: '{321C8C3F-0156-40C1-AE42-D59761FB9B6C}'
+  useCompareNetObjects: true 
+  disallowAdditionalPropertiesIfNotPresent: false
+  nullableReferenceTypes: true
+  equatable: true
+  targetFramework: net10.0
+  modelPropertySorting: alphabetical
+  operationParameterSorting: alphabetical
diff --git a/bin/configs/csharp-generichost-net10-useDateTimeForDate.yaml b/bin/configs/csharp-generichost-net10-useDateTimeForDate.yaml
@@ -0,0 +1,11 @@
+# for csharp generichost
+generatorName: csharp
+outputDir: samples/client/petstore/csharp/generichost/net10/UseDateTimeForDate
+inputSpec: modules/openapi-generator/src/test/resources/3_0/csharp/dates-api.yaml
+templateDir: modules/openapi-generator/src/main/resources/csharp
+additionalProperties:
+  packageGuid: '{2E60EF87-DB0B-4D01-A36E-F5E90F7EC757}'
+  useDateTimeForDate: true
+  targetFramework: net10.0
+  modelPropertySorting: alphabetical
+  operationParameterSorting: alphabetical
diff --git a/bin/configs/csharp-generichost-net10.yaml b/bin/configs/csharp-generichost-net10.yaml
@@ -0,0 +1,14 @@
+# for csharp generichost
+generatorName: csharp
+outputDir: samples/client/petstore/csharp/generichost/net10/Petstore
+inputSpec: modules/openapi-generator/src/test/resources/3_0/csharp/petstore-with-fake-endpoints-models-for-testing-with-http-signature.yaml
+templateDir: modules/openapi-generator/src/main/resources/csharp
+additionalProperties:
+  packageGuid: '{321C8C3F-0156-40C1-AE42-D59761FB9B6C}'
+  useCompareNetObjects: true 
+  disallowAdditionalPropertiesIfNotPresent: false
+  nullableReferenceTypes: false
+  equatable: true
+  targetFramework: net10.0
+  modelPropertySorting: alphabetical
+  operationParameterSorting: alphabetical
diff --git a/bin/configs/csharp-httpclient-net10-nonPublicApi.yaml b/bin/configs/csharp-httpclient-net10-nonPublicApi.yaml
@@ -0,0 +1,14 @@
+# for .net standard httpclient
+generatorName: csharp
+outputDir: samples/client/petstore/csharp/httpclient/net10/Petstore-nonPublicApi
+inputSpec: modules/openapi-generator/src/test/resources/3_0/petstore-addpet-only.yaml
+templateDir: modules/openapi-generator/src/main/resources/csharp
+library: httpclient
+additionalProperties:
+  packageGuid: '{321C8C3F-0156-40C1-AE42-D59761FB9B6C}'
+  useCompareNetObjects: true 
+  disallowAdditionalPropertiesIfNotPresent: false
+  useOneOfDiscriminatorLookup: true
+  targetFramework: net10.0
+  equatable: true
+  nonPublicApi: true
diff --git a/bin/configs/csharp-httpclient-net10.yaml b/bin/configs/csharp-httpclient-net10.yaml
@@ -0,0 +1,13 @@
+# for .net standard httpclient
+generatorName: csharp
+outputDir: samples/client/petstore/csharp/httpclient/net10/Petstore
+inputSpec: modules/openapi-generator/src/test/resources/3_0/csharp/petstore-with-fake-endpoints-models-for-testing-with-http-signature.yaml
+templateDir: modules/openapi-generator/src/main/resources/csharp
+library: httpclient
+additionalProperties:
+  packageGuid: '{321C8C3F-0156-40C1-AE42-D59761FB9B6C}'
+  useCompareNetObjects: true 
+  disallowAdditionalPropertiesIfNotPresent: false
+  useOneOfDiscriminatorLookup: true
+  targetFramework: net10.0
+  equatable: true
diff --git a/bin/configs/csharp-restsharp-net10.yaml b/bin/configs/csharp-restsharp-net10.yaml
@@ -0,0 +1,15 @@
+# for .net standard
+generatorName: csharp
+library: restsharp
+outputDir: samples/client/petstore/csharp/restsharp/net10/EnumMappings
+inputSpec: modules/openapi-generator/src/test/resources/3_0/csharp/petstore-with-fake-endpoints-models-for-testing-with-http-signature-oneof-primitive-types.yaml
+templateDir: modules/openapi-generator/src/main/resources/csharp
+additionalProperties:
+  packageGuid: '{321C8C3F-0156-40C1-AE42-D59761FB9B6C}'
+  useCompareNetObjects: true 
+  disallowAdditionalPropertiesIfNotPresent: false
+  useOneOfDiscriminatorLookup: true
+  targetFramework: net10.0
+  equatable: true
+enumNameMappings:
+  delivered: Shipped
diff --git a/bin/configs/csharp-unityWebRequest-net10.yaml b/bin/configs/csharp-unityWebRequest-net10.yaml
@@ -0,0 +1,9 @@
+# for .net Unity
+generatorName: csharp
+outputDir: samples/client/petstore/csharp/unityWebRequest/net10/Petstore
+inputSpec: modules/openapi-generator/src/test/resources/3_0/csharp/petstore-with-fake-endpoints-models-for-testing-with-http-signature.yaml
+templateDir: modules/openapi-generator/src/main/resources/csharp
+library: unityWebRequest
+additionalProperties:
+  targetFramework: net10.0
+  equatable: true
diff --git a/docs/generators/csharp.md b/docs/generators/csharp.md
@@ -46,7 +46,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 |packageVersion|C# package version.| |1.0.0|
 |returnICollection|Return ICollection&lt;T&gt; instead of the concrete type.| |false|
 |sourceFolder|source folder for generated code| |src|
-|targetFramework|The target .NET framework version. To target multiple frameworks, use `;` as the separator, e.g. `netstandard2.1;netcoreapp3.1`|<dl><dt>**netstandard1.3**</dt><dd>.NET Standard 1.3</dd><dt>**netstandard1.4**</dt><dd>.NET Standard 1.4</dd><dt>**netstandard1.5**</dt><dd>.NET Standard 1.5</dd><dt>**netstandard1.6**</dt><dd>.NET Standard 1.6</dd><dt>**netstandard2.0**</dt><dd>.NET Standard 2.0</dd><dt>**netstandard2.1**</dt><dd>.NET Standard 2.1</dd><dt>**net47**</dt><dd>.NET Framework 4.7</dd><dt>**net48**</dt><dd>.NET Framework 4.8</dd><dt>**net8.0**</dt><dd>.NET 8.0 (End of Support 10 November 2026)</dd><dt>**net9.0**</dt><dd>.NET 9.0 (End of Support 12 May 2026)</dd></dl>|net9.0|
+|targetFramework|The target .NET framework version. To target multiple frameworks, use `;` as the separator, e.g. `netstandard2.1;netcoreapp3.1`|<dl><dt>**netstandard1.3**</dt><dd>.NET Standard 1.3</dd><dt>**netstandard1.4**</dt><dd>.NET Standard 1.4</dd><dt>**netstandard1.5**</dt><dd>.NET Standard 1.5</dd><dt>**netstandard1.6**</dt><dd>.NET Standard 1.6</dd><dt>**netstandard2.0**</dt><dd>.NET Standard 2.0</dd><dt>**netstandard2.1**</dt><dd>.NET Standard 2.1</dd><dt>**net47**</dt><dd>.NET Framework 4.7</dd><dt>**net48**</dt><dd>.NET Framework 4.8</dd><dt>**net8.0**</dt><dd>.NET 8.0 (End of Support 10 November 2026)</dd><dt>**net9.0**</dt><dd>.NET 9.0 (End of Support 10 November 2026)</dd><dt>**net10.0**</dt><dd>.NET 10.0 (End of Support 14 November 2028)</dd></dl>|net10.0|
 |useCollection|Deserialize array types to Collection&lt;T&gt; instead of List&lt;T&gt;.| |false|
 |useDateTimeForDate|Use DateTime to model date properties even if DateOnly supported. (.net 6.0+ only)| |false|
 |useDateTimeOffset|Use DateTimeOffset to model date-time properties| |false|

diff --git a/...enapi-generator/src/main/java/org/openapitools/codegen/languages/CSharpClientCodegen.java b/...enapi-generator/src/main/java/org/openapitools/codegen/languages/CSharpClientCodegen.java
@@ -77,6 +77,7 @@ public class CSharpClientCodegen extends AbstractCSharpCodegen {
     protected static final String NET_70_OR_LATER = "net70OrLater";
     protected static final String NET_80_OR_LATER = "net80OrLater";
     protected static final String NET_90_OR_LATER = "net90OrLater";
+    protected static final String NET_10_OR_LATER = "net10OrLater";
 
     @SuppressWarnings("hiding")
     private final Logger LOGGER = LoggerFactory.getLogger(CSharpClientCodegen.class);
@@ -90,7 +91,8 @@ public class CSharpClientCodegen extends AbstractCSharpCodegen {
             FrameworkStrategy.NETFRAMEWORK_4_7,
             FrameworkStrategy.NETFRAMEWORK_4_8,
             FrameworkStrategy.NET_8_0,
-            FrameworkStrategy.NET_9_0
+            FrameworkStrategy.NET_9_0,
+            FrameworkStrategy.NET_10
     );
     private static FrameworkStrategy latestFramework = frameworkStrategies.get(frameworkStrategies.size() - 1);
     protected final Map<String, String> frameworks;
@@ -1448,8 +1450,11 @@ private static abstract class FrameworkStrategy {
         };
         static FrameworkStrategy NET_8_0 = new FrameworkStrategy("net8.0", ".NET 8.0 (End of Support 10 November 2026)", "net8.0", Boolean.FALSE) {
         };
-        static FrameworkStrategy NET_9_0 = new FrameworkStrategy("net9.0", ".NET 9.0 (End of Support 12 May 2026)", "net9.0", Boolean.FALSE) {
+        static FrameworkStrategy NET_9_0 = new FrameworkStrategy("net9.0", ".NET 9.0 (End of Support 10 November 2026)", "net9.0", Boolean.FALSE) {
         };
+        static FrameworkStrategy NET_10 = new FrameworkStrategy("net10.0", ".NET 10.0 (End of Support 14 November 2028)", "net10.0", Boolean.FALSE) {
+        };
+
         protected String name;
         protected String description;
         protected String testTargetFramework;
@@ -1580,6 +1585,19 @@ protected void configureAdditionalPropertiesForFrameworks(final Map<String, Obje
                 properties.put(NET_70_OR_LATER, true);
                 properties.put(NET_80_OR_LATER, true);
                 properties.put(NET_90_OR_LATER, true);
+            } else if (strategies.stream().anyMatch(p -> "net10.0".equals(p.name))) {
+                properties.put(NET_STANDARD_14_OR_LATER, true);
+                properties.put(NET_STANDARD_15_OR_LATER, true);
+                properties.put(NET_STANDARD_16_OR_LATER, true);
+                properties.put(NET_STANDARD_20_OR_LATER, true);
+                properties.put(NET_STANDARD_21_OR_LATER, true);
+                properties.put(NET_47_OR_LATER, true);
+                properties.put(NET_48_OR_LATER, true);
+                properties.put(NET_60_OR_LATER, true);
+                properties.put(NET_70_OR_LATER, true);
+                properties.put(NET_80_OR_LATER, true);
+                properties.put(NET_90_OR_LATER, true);
+                properties.put(NET_10_OR_LATER, true);
             } else {
                 throw new RuntimeException("Unhandled case");
             }