[csharp][generichost] Better file support

modules/openapi-generator/src/main/resources/csharp/libraries/generichost/api.mustache

@@ -471,14 +471,15 @@ namespace {{packageName}}.{{apiPackage}}
                     {{/headerParams}}
                     {{#formParams}}
                     {{#-first}}
-                    MultipartContent multipartContentLocalVar = new MultipartContent();
+                    MultipartFormDataContent multipartContentLocalVar = new MultipartFormDataContent();
 
                     httpRequestMessageLocalVar.Content = multipartContentLocalVar;
 
                     List<KeyValuePair<string{{nrt?}}, string{{nrt?}}>> formParameterLocalVars = new List<KeyValuePair<string{{nrt?}}, string{{nrt?}}>>();
 
-                    multipartContentLocalVar.Add(new FormUrlEncodedContent(formParameterLocalVars));{{/-first}}{{^isFile}}{{#required}}
-
+                    {{/-first}}
+                    {{^isFile}}
+                    {{#required}}
                     formParameterLocalVars.Add(new KeyValuePair<string{{nrt?}}, string{{nrt?}}>("{{baseName}}", ClientUtils.ParameterToString({{paramName}})));
 
                     {{/required}}
@@ -490,16 +491,46 @@ namespace {{packageName}}.{{apiPackage}}
                     {{/isFile}}
                     {{#isFile}}
                     {{#required}}
-                    multipartContentLocalVar.Add(new StreamContent({{paramName}}));
+                    {{#isContainer}}
+                    foreach (global::System.IO.Stream streamLocalVar in {{paramName}})
+                    {
+                        var streamContentLocalVar = new StreamContent(streamLocalVar);
+                        multipartContentLocalVar.Add(streamContentLocalVar, "{{baseName}}");
+                    }
+
+                    {{/isContainer}}
+                    {{^isContainer}}
+                    var streamContentLocalVar = new StreamContent({{paramName}});
+                    multipartContentLocalVar.Add(streamContentLocalVar, "{{baseName}}");
 
+                    {{/isContainer}}
                     {{/required}}
                     {{^required}}
                     if ({{paramName}}.IsSet)
-                        multipartContentLocalVar.Add(new StreamContent({{paramName}}.Value));
+                    {
+                        {{#isContainer}}
+                        foreach (global::System.IO.Stream streamLocalVar in {{paramName}}.Value)
+                        {
+                            var streamContentLocalVar = new StreamContent(streamLocalVar);
+                            multipartContentLocalVar.Add(streamContentLocalVar, "{{baseName}}");
+                        }
+                        {{/isContainer}}
+                        {{^isContainer}}
+                        var streamContentLocalVar = new StreamContent({{paramName}}.Value);
+                        multipartContentLocalVar.Add(streamContentLocalVar, "{{baseName}}");
+                        {{/isContainer}}
+                    }
 
                     {{/required}}
                     {{/isFile}}
                     {{/formParams}}
+                    {{#formParams}}
+                    {{#-first}}
+                    if (formParameterLocalVars.Count > 0)
+                        multipartContentLocalVar.Add(new FormUrlEncodedContent(formParameterLocalVars));
+
+                    {{/-first}}
+                    {{/formParams}}
                     {{#bodyParam}}
                     {{#required}}
                     httpRequestMessageLocalVar.Content = ({{paramName}}{{^required}}.Value{{/required}} as object) is System.IO.Stream stream
@@ -587,10 +618,12 @@ namespace {{packageName}}.{{apiPackage}}
                     {{#consumes}}
                     {{#-first}}
 
+                    {{^formParams}}
                     string{{nrt?}} contentTypeLocalVar = ClientUtils.SelectHeaderContentType(contentTypes);
 
                     if (contentTypeLocalVar != null && httpRequestMessageLocalVar.Content != null)
                         httpRequestMessageLocalVar.Content.Headers.ContentType = new MediaTypeHeaderValue(contentTypeLocalVar);
+                    {{/formParams}}
 
                     {{/-first}}
                     {{/consumes}}

modules/openapi-generator/src/test/resources/3_0/csharp/petstore-with-fake-endpoints-models-for-testing-with-http-signature.yaml

@@ -316,6 +316,46 @@ paths:
                   description: file to upload
                   type: string
                   format: binary
+  '/pet/{petId}/uploadImages':
+    post:
+      tags:
+        - pet
+      summary: uploads an images
+      description: ''
+      operationId: uploadFiles
+      parameters:
+        - name: petId
+          in: path
+          description: ID of pet to update
+          required: true
+          schema:
+            type: integer
+            format: int64
+      responses:
+        '200':
+          description: successful operation
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/ApiResponse'
+      security:
+        - petstore_auth:
+            - 'write:pets'
+            - 'read:pets'
+      requestBody:
+        required: true
+        content:
+          multipart/form-data:
+            schema:
+              type: object
+              properties:
+                files:
+                  type: array
+                  items:
+                    type: string
+                    format: binary
+              required:
+                - files
   /store/inventory:
     get:
       tags:

samples/client/petstore/csharp/generichost/net10/FormModels/api/openapi.yaml

@@ -326,6 +326,40 @@ paths:
       summary: uploads an image
       tags:
       - pet
+  /pet/{petId}/uploadImages:
+    post:
+      description: ""
+      operationId: uploadFiles
+      parameters:
+      - description: ID of pet to update
+        explode: false
+        in: path
+        name: petId
+        required: true
+        schema:
+          format: int64
+          type: integer
+        style: simple
+      requestBody:
+        content:
+          multipart/form-data:
+            schema:
+              $ref: "#/components/schemas/uploadFiles_request"
+        required: true
+      responses:
+        "200":
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/ApiResponse"
+          description: successful operation
+      security:
+      - petstore_auth:
+        - write:pets
+        - read:pets
+      summary: uploads an images
+      tags:
+      - pet
   /store/inventory:
     get:
       description: Returns a map of status codes to quantities
@@ -2748,6 +2782,16 @@ components:
           format: binary
           type: string
       type: object
+    uploadFiles_request:
+      properties:
+        files:
+          items:
+            format: binary
+            type: string
+          type: array
+      required:
+      - files
+      type: object
     testEnumParameters_request_enum_form_string_array_inner:
       default: $
       enum:

samples/client/petstore/csharp/generichost/net10/FormModels/docs/apis/PetApi.md

@@ -13,6 +13,7 @@ All URIs are relative to *http://petstore.swagger.io:80/v2*
 | [**UpdatePetWithForm**](PetApi.md#updatepetwithform) | **POST** /pet/{petId} | Updates a pet in the store with form data |
 | [**UploadFile**](PetApi.md#uploadfile) | **POST** /pet/{petId}/uploadImage | uploads an image |
 | [**UploadFileWithRequiredFile**](PetApi.md#uploadfilewithrequiredfile) | **POST** /fake/{petId}/uploadImageWithRequiredFile | uploads an image (required) |
+| [**UploadFiles**](PetApi.md#uploadfiles) | **POST** /pet/{petId}/uploadImages | uploads an images |
 
 <a id="addpet"></a>
 # **AddPet**
@@ -341,3 +342,38 @@ uploads an image (required)
 
 [[Back to top]](#) [[Back to API list]](../../README.md#documentation-for-api-endpoints) [[Back to Model list]](../../README.md#documentation-for-models) [[Back to README]](../../README.md)
 
+<a id="uploadfiles"></a>
+# **UploadFiles**
+> ApiResponse UploadFiles (List<System.IO.Stream> files, long petId)
+
+uploads an images
+
+
+### Parameters
+
+| Name | Type | Description | Notes |
+|------|------|-------------|-------|
+| **files** | **List&lt;System.IO.Stream&gt;** |  |  |
+| **petId** | **long** | ID of pet to update |  |
+
+### Return type
+
+[**ApiResponse**](ApiResponse.md)
+
+### Authorization
+
+[petstore_auth](../README.md#petstore_auth)
+
+### HTTP request headers
+
+ - **Content-Type**: multipart/form-data
+ - **Accept**: application/json
+
+
+### HTTP response details
+| Status code | Description | Response headers |
+|-------------|-------------|------------------|
+| **200** | successful operation |  -  |
+
+[[Back to top]](#) [[Back to API list]](../../README.md#documentation-for-api-endpoints) [[Back to Model list]](../../README.md#documentation-for-models) [[Back to README]](../../README.md)
+

samples/client/petstore/csharp/generichost/net10/FormModels/src/Org.OpenAPITools.Test/Api/PetApiTests.cs

@@ -90,7 +90,7 @@
         public async Task FindPetsByTagsAsyncTest()
         {
             List<string> tags = default;
             var response = await _instance.FindPetsByTagsAsync(tags);
             var model = response.Ok();
             Assert.IsType<List<Pet>>(model);
         }
@@ -156,5 +156,18 @@
             var model = response.Ok();
             Assert.IsType<ApiResponse>(model);
         }
+
+        /// <summary>
+        /// Test UploadFiles
+        /// </summary>
+        [Fact (Skip = "not implemented")]
+        public async Task UploadFilesAsyncTest()
+        {
+            List<System.IO.Stream> files = default;
+            long petId = default;
+            var response = await _instance.UploadFilesAsync(files, petId);
+            var model = response.Ok();
+            Assert.IsType<ApiResponse>(model);
+        }
     }
 }

samples/client/petstore/csharp/generichost/net10/FormModels/src/Org.OpenAPITools/Api/DefaultApi.cs

@@ -764,27 +764,23 @@ public async Task<IGetCountryApiResponse> GetCountryAsync(string country, System
                         ? "/country"
                         : string.Concat(HttpClient.BaseAddress.AbsolutePath, "/country");
 
-                    MultipartContent multipartContentLocalVar = new MultipartContent();
+                    MultipartFormDataContent multipartContentLocalVar = new MultipartFormDataContent();
 
                     httpRequestMessageLocalVar.Content = multipartContentLocalVar;
 
                     List<KeyValuePair<string, string>> formParameterLocalVars = new List<KeyValuePair<string, string>>();
 
-                    multipartContentLocalVar.Add(new FormUrlEncodedContent(formParameterLocalVars));
-
                     formParameterLocalVars.Add(new KeyValuePair<string, string>("country", ClientUtils.ParameterToString(country)));
 
+                    if (formParameterLocalVars.Count > 0)
+                        multipartContentLocalVar.Add(new FormUrlEncodedContent(formParameterLocalVars));
+
                     httpRequestMessageLocalVar.RequestUri = uriBuilderLocalVar.Uri;
 
                     string[] contentTypes = new string[] {
                         "application/x-www-form-urlencoded"
                     };
 
-                    string contentTypeLocalVar = ClientUtils.SelectHeaderContentType(contentTypes);
-
-                    if (contentTypeLocalVar != null && httpRequestMessageLocalVar.Content != null)
-                        httpRequestMessageLocalVar.Content.Headers.ContentType = new MediaTypeHeaderValue(contentTypeLocalVar);
-
                     httpRequestMessageLocalVar.Method = HttpMethod.Post;
 
                     DateTime requestedAtLocalVar = DateTime.UtcNow;