ContentType selection fix for csharp. (#6633)

* ContentType selection fix for csharp.
Updated to reflect java implementation. Previously any request body of type string was having the content type overridden to 'application/json'.  This prevented custom json ContentTypes

* updated the petshop codegen for C#

* Fixed content type selection test for csharp

* Replaced tabs with 4 spaces

* Removed trailing space / string comparison

modules/swagger-codegen/src/main/resources/csharp/ApiClient.mustache

@@ -165,24 +165,12 @@ namespace {{packageName}}.Client
 
             if (postBody != null) // http body (model or byte[]) parameter
             {
-                if (postBody.GetType() == typeof(String))
-                {
-                    {{#netStandard}}
-                    request.AddParameter(new Parameter { Value = postBody, Type = ParameterType.RequestBody, ContentType = "application/json" });
-                    {{/netStandard}}
-                    {{^netStandard}}
-                    request.AddParameter("application/json", postBody, ParameterType.RequestBody);
-                    {{/netStandard}}
-                }
-                else if (postBody.GetType() == typeof(byte[]))
-                {
-                    {{#netStandard}}
-                    request.AddParameter(new Parameter { Value = postBody, Type = ParameterType.RequestBody, ContentType = contentType });
-                    {{/netStandard}}
-                    {{^netStandard}}
-                    request.AddParameter(contentType, postBody, ParameterType.RequestBody);
-                    {{/netStandard}}
-                }
+                {{#netStandard}}
+                request.AddParameter(new Parameter { Value = postBody, Type = ParameterType.RequestBody, ContentType = contentType });
+                {{/netStandard}}
+                {{^netStandard}}
+                request.AddParameter(contentType, postBody, ParameterType.RequestBody);
+                {{/netStandard}}
             }
 
             return request;
@@ -399,9 +387,25 @@ namespace {{packageName}}.Client
             }
         }
 
+        /// <summary>
+        ///Check if the given MIME is a JSON MIME.
+        ///JSON MIME examples:
+        ///    application/json
+        ///    application/json; charset=UTF8
+        ///    APPLICATION/JSON
+        ///    application/vnd.company+json
+        /// </summary>
+        /// <param name="mime">MIME</param>
+        /// <returns>Returns True if MIME type is json.</returns>
+        public bool IsJsonMime(String mime)
+        {
+            var jsonRegex = new Regex("(?i)^(application/json|[^;/ \t]+/[^;/ \t]+[+]json)[ \t]*(;.*)?$");
+            return mime != null && (jsonRegex.IsMatch(mime) || mime.Equals("application/json-patch+json"));
+        }
+
         /// <summary>
         /// Select the Content-Type header's value from the given content-type array:
-        /// if JSON exists in the given array, use it;
+        /// if JSON type exists in the given array, use it;
         /// otherwise use the first one defined in 'consumes'
         /// </summary>
         /// <param name="contentTypes">The Content-Type array to select from.</param>
@@ -409,11 +413,14 @@ namespace {{packageName}}.Client
         public String SelectHeaderContentType(String[] contentTypes)
         {
             if (contentTypes.Length == 0)
-                return null;
-
-            if (contentTypes.Contains("application/json", StringComparer.OrdinalIgnoreCase))
                 return "application/json";
 
+            foreach (var contentType in contentTypes)
+            {
+                if (IsJsonMime(contentType.ToLower()))
+                    return contentType;
+            }
+
             return contentTypes[0]; // use the first content type specified in 'consumes'
         }
 

samples/client/petstore/csharp/SwaggerClient/README.md

@@ -68,17 +68,18 @@ namespace Example
         public void main()
         {
 
-            var apiInstance = new FakeApi();
-            var body = new OuterBoolean(); // OuterBoolean | Input boolean as post body (optional) 
+            var apiInstance = new AnotherFakeApi();
+            var body = new ModelClient(); // ModelClient | client model
 
             try
             {
-                OuterBoolean result = apiInstance.FakeOuterBooleanSerialize(body);
+                // To test special tags
+                ModelClient result = apiInstance.TestSpecialTags(body);
                 Debug.WriteLine(result);
             }
             catch (Exception e)
             {
-                Debug.Print("Exception when calling FakeApi.FakeOuterBooleanSerialize: " + e.Message );
+                Debug.Print("Exception when calling AnotherFakeApi.TestSpecialTags: " + e.Message );
             }
 
         }
@@ -93,6 +94,7 @@ All URIs are relative to *http://petstore.swagger.io:80/v2*
 
 Class | Method | HTTP request | Description
 ------------ | ------------- | ------------- | -------------
+*AnotherFakeApi* | [**TestSpecialTags**](docs/AnotherFakeApi.md#testspecialtags) | **PATCH** /another-fake/dummy | To test special tags
 *FakeApi* | [**FakeOuterBooleanSerialize**](docs/FakeApi.md#fakeouterbooleanserialize) | **POST** /fake/outer/boolean | 
 *FakeApi* | [**FakeOuterCompositeSerialize**](docs/FakeApi.md#fakeoutercompositeserialize) | **POST** /fake/outer/composite | 
 *FakeApi* | [**FakeOuterNumberSerialize**](docs/FakeApi.md#fakeouternumberserialize) | **POST** /fake/outer/number | 
@@ -101,7 +103,7 @@ Class | Method | HTTP request | Description
 *FakeApi* | [**TestEndpointParameters**](docs/FakeApi.md#testendpointparameters) | **POST** /fake | Fake endpoint for testing various parameters 假端點 偽のエンドポイント 가짜 엔드 포인트 
 *FakeApi* | [**TestEnumParameters**](docs/FakeApi.md#testenumparameters) | **GET** /fake | To test enum parameters
 *FakeApi* | [**TestJsonFormData**](docs/FakeApi.md#testjsonformdata) | **GET** /fake/jsonFormData | test json serialization of form data
-*Fake_classname_tags123Api* | [**TestClassname**](docs/Fake_classname_tags123Api.md#testclassname) | **PATCH** /fake_classname_test | To test class name in snake case
+*FakeClassnameTags123Api* | [**TestClassname**](docs/FakeClassnameTags123Api.md#testclassname) | **PATCH** /fake_classname_test | To test class name in snake case
 *PetApi* | [**AddPet**](docs/PetApi.md#addpet) | **POST** /pet | Add a new pet to the store
 *PetApi* | [**DeletePet**](docs/PetApi.md#deletepet) | **DELETE** /pet/{petId} | Deletes a pet
 *PetApi* | [**FindPetsByStatus**](docs/PetApi.md#findpetsbystatus) | **GET** /pet/findByStatus | Finds Pets by status

samples/client/petstore/csharp/SwaggerClient/docs/AnotherFakeApi.md

@@ -0,0 +1,70 @@
+# IO.Swagger.Api.AnotherFakeApi
+
+All URIs are relative to *http://petstore.swagger.io:80/v2*
+
+Method | HTTP request | Description
+------------- | ------------- | -------------
+[**TestSpecialTags**](AnotherFakeApi.md#testspecialtags) | **PATCH** /another-fake/dummy | To test special tags
+
+
+<a name="testspecialtags"></a>
+# **TestSpecialTags**
+> ModelClient TestSpecialTags (ModelClient body)
+
+To test special tags
+
+To test special tags
+
+### Example
+```csharp
+using System;
+using System.Diagnostics;
+using IO.Swagger.Api;
+using IO.Swagger.Client;
+using IO.Swagger.Model;
+
+namespace Example
+{
+    public class TestSpecialTagsExample
+    {
+        public void main()
+        {
+            var apiInstance = new AnotherFakeApi();
+            var body = new ModelClient(); // ModelClient | client model
+
+            try
+            {
+                // To test special tags
+                ModelClient result = apiInstance.TestSpecialTags(body);
+                Debug.WriteLine(result);
+            }
+            catch (Exception e)
+            {
+                Debug.Print("Exception when calling AnotherFakeApi.TestSpecialTags: " + e.Message );
+            }
+        }
+    }
+}
+```
+
+### Parameters
+
+Name | Type | Description  | Notes
+------------- | ------------- | ------------- | -------------
+ **body** | [**ModelClient**](ModelClient.md)| client model | 
+
+### Return type
+
+[**ModelClient**](ModelClient.md)
+
+### Authorization
+
+No authorization required
+
+### HTTP request headers
+
+ - **Content-Type**: application/json
+ - **Accept**: application/json
+
+[[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/SwaggerClient/docs/FakeClassnameTags123Api.md

@@ -0,0 +1,73 @@
+# IO.Swagger.Api.FakeClassnameTags123Api
+
+All URIs are relative to *http://petstore.swagger.io:80/v2*
+
+Method | HTTP request | Description
+------------- | ------------- | -------------
+[**TestClassname**](FakeClassnameTags123Api.md#testclassname) | **PATCH** /fake_classname_test | To test class name in snake case
+
+
+<a name="testclassname"></a>
+# **TestClassname**
+> ModelClient TestClassname (ModelClient body)
+
+To test class name in snake case
+
+### Example
+```csharp
+using System;
+using System.Diagnostics;
+using IO.Swagger.Api;
+using IO.Swagger.Client;
+using IO.Swagger.Model;
+
+namespace Example
+{
+    public class TestClassnameExample
+    {
+        public void main()
+        {
+            // Configure API key authorization: api_key_query
+            Configuration.Default.AddApiKey("api_key_query", "YOUR_API_KEY");
+            // Uncomment below to setup prefix (e.g. Bearer) for API key, if needed
+            // Configuration.Default.AddApiKeyPrefix("api_key_query", "Bearer");
+
+            var apiInstance = new FakeClassnameTags123Api();
+            var body = new ModelClient(); // ModelClient | client model
+
+            try
+            {
+                // To test class name in snake case
+                ModelClient result = apiInstance.TestClassname(body);
+                Debug.WriteLine(result);
+            }
+            catch (Exception e)
+            {
+                Debug.Print("Exception when calling FakeClassnameTags123Api.TestClassname: " + e.Message );
+            }
+        }
+    }
+}
+```
+
+### Parameters
+
+Name | Type | Description  | Notes
+------------- | ------------- | ------------- | -------------
+ **body** | [**ModelClient**](ModelClient.md)| client model | 
+
+### Return type
+
+[**ModelClient**](ModelClient.md)
+
+### Authorization
+
+[api_key_query](../README.md#api_key_query)
+
+### HTTP request headers
+
+ - **Content-Type**: application/json
+ - **Accept**: application/json
+
+[[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/SwaggerClient/src/IO.Swagger.Test/Api/AnotherFakeApiTests.cs

@@ -0,0 +1,81 @@
+/* 
+ * Swagger Petstore
+ *
+ * This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\
+ *
+ * OpenAPI spec version: 1.0.0
+ * Contact: apiteam@swagger.io
+ * Generated by: https://github.com/swagger-api/swagger-codegen.git
+ */
+
+using System;
+using System.IO;
+using System.Collections.Generic;
+using System.Collections.ObjectModel;
+using System.Linq;
+using System.Reflection;
+using RestSharp;
+using NUnit.Framework;
+
+using IO.Swagger.Client;
+using IO.Swagger.Api;
+using IO.Swagger.Model;
+
+namespace IO.Swagger.Test
+{
+    /// <summary>
+    ///  Class for testing AnotherFakeApi
+    /// </summary>
+    /// <remarks>
+    /// This file is automatically generated by Swagger Codegen.
+    /// Please update the test case below to test the API endpoint.
+    /// </remarks>
+    [TestFixture]
+    public class AnotherFakeApiTests
+    {
+        private AnotherFakeApi instance;
+
+        /// <summary>
+        /// Setup before each unit test
+        /// </summary>
+        [SetUp]
+        public void Init()
+        {
+            instance = new AnotherFakeApi();
+        }
+
+        /// <summary>
+        /// Clean up after each unit test
+        /// </summary>
+        [TearDown]
+        public void Cleanup()
+        {
+
+        }
+
+        /// <summary>
+        /// Test an instance of AnotherFakeApi
+        /// </summary>
+        [Test]
+        public void InstanceTest()
+        {
+            // TODO uncomment below to test 'IsInstanceOfType' AnotherFakeApi
+            //Assert.IsInstanceOfType(typeof(AnotherFakeApi), instance, "instance is a AnotherFakeApi");
+        }
+
+        
+        /// <summary>
+        /// Test TestSpecialTags
+        /// </summary>
+        [Test]
+        public void TestSpecialTagsTest()
+        {
+            // TODO uncomment below to test the method and replace null with proper value
+            //ModelClient body = null;
+            //var response = instance.TestSpecialTags(body);
+            //Assert.IsInstanceOf<ModelClient> (response, "response is ModelClient");
+        }
+        
+    }
+
+}

samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger.Test/Api/FakeClassnameTags123ApiTests.cs

@@ -0,0 +1,81 @@
+/* 
+ * Swagger Petstore
+ *
+ * This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\
+ *
+ * OpenAPI spec version: 1.0.0
+ * Contact: apiteam@swagger.io
+ * Generated by: https://github.com/swagger-api/swagger-codegen.git
+ */
+
+using System;
+using System.IO;
+using System.Collections.Generic;
+using System.Collections.ObjectModel;
+using System.Linq;
+using System.Reflection;
+using RestSharp;
+using NUnit.Framework;
+
+using IO.Swagger.Client;
+using IO.Swagger.Api;
+using IO.Swagger.Model;
+
+namespace IO.Swagger.Test
+{
+    /// <summary>
+    ///  Class for testing FakeClassnameTags123Api
+    /// </summary>
+    /// <remarks>
+    /// This file is automatically generated by Swagger Codegen.
+    /// Please update the test case below to test the API endpoint.
+    /// </remarks>
+    [TestFixture]
+    public class FakeClassnameTags123ApiTests
+    {
+        private FakeClassnameTags123Api instance;
+
+        /// <summary>
+        /// Setup before each unit test
+        /// </summary>
+        [SetUp]
+        public void Init()
+        {
+            instance = new FakeClassnameTags123Api();
+        }
+
+        /// <summary>
+        /// Clean up after each unit test
+        /// </summary>
+        [TearDown]
+        public void Cleanup()
+        {
+
+        }
+
+        /// <summary>
+        /// Test an instance of FakeClassnameTags123Api
+        /// </summary>
+        [Test]
+        public void InstanceTest()
+        {
+            // TODO uncomment below to test 'IsInstanceOfType' FakeClassnameTags123Api
+            //Assert.IsInstanceOfType(typeof(FakeClassnameTags123Api), instance, "instance is a FakeClassnameTags123Api");
+        }
+
+        
+        /// <summary>
+        /// Test TestClassname
+        /// </summary>
+        [Test]
+        public void TestClassnameTest()
+        {
+            // TODO uncomment below to test the method and replace null with proper value
+            //ModelClient body = null;
+            //var response = instance.TestClassname(body);
+            //Assert.IsInstanceOf<ModelClient> (response, "response is ModelClient");
+        }
+        
+    }
+
+}

samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger.Test/Client/ApiClientTests.cs

@@ -41,7 +41,7 @@ namespace IO.Swagger.Test
 			Assert.AreEqual("application/xml", api.SelectHeaderContentType (contentTypes));
 
 			contentTypes = new String[] {};
-			Assert.IsNull(api.SelectHeaderContentType (contentTypes));	
+			Assert.AreEqual("application/json", api.SelectHeaderContentType (contentTypes));
 		}
 
 		/// <summary>

samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger/Api/AnotherFakeApi.cs

@@ -0,0 +1,321 @@
+/* 
+ * Swagger Petstore
+ *
+ * This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\
+ *
+ * OpenAPI spec version: 1.0.0
+ * Contact: apiteam@swagger.io
+ * Generated by: https://github.com/swagger-api/swagger-codegen.git
+ */
+
+using System;
+using System.Collections.Generic;
+using System.Collections.ObjectModel;
+using System.Linq;
+using RestSharp;
+using IO.Swagger.Client;
+using IO.Swagger.Model;
+
+namespace IO.Swagger.Api
+{
+    /// <summary>
+    /// Represents a collection of functions to interact with the API endpoints
+    /// </summary>
+    public interface IAnotherFakeApi : IApiAccessor
+    {
+        #region Synchronous Operations
+        /// <summary>
+        /// To test special tags
+        /// </summary>
+        /// <remarks>
+        /// To test special tags
+        /// </remarks>
+        /// <exception cref="IO.Swagger.Client.ApiException">Thrown when fails to make API call</exception>
+        /// <param name="body">client model</param>
+        /// <returns>ModelClient</returns>
+        ModelClient TestSpecialTags (ModelClient body);
+
+        /// <summary>
+        /// To test special tags
+        /// </summary>
+        /// <remarks>
+        /// To test special tags
+        /// </remarks>
+        /// <exception cref="IO.Swagger.Client.ApiException">Thrown when fails to make API call</exception>
+        /// <param name="body">client model</param>
+        /// <returns>ApiResponse of ModelClient</returns>
+        ApiResponse<ModelClient> TestSpecialTagsWithHttpInfo (ModelClient body);
+        #endregion Synchronous Operations
+        #region Asynchronous Operations
+        /// <summary>
+        /// To test special tags
+        /// </summary>
+        /// <remarks>
+        /// To test special tags
+        /// </remarks>
+        /// <exception cref="IO.Swagger.Client.ApiException">Thrown when fails to make API call</exception>
+        /// <param name="body">client model</param>
+        /// <returns>Task of ModelClient</returns>
+        System.Threading.Tasks.Task<ModelClient> TestSpecialTagsAsync (ModelClient body);
+
+        /// <summary>
+        /// To test special tags
+        /// </summary>
+        /// <remarks>
+        /// To test special tags
+        /// </remarks>
+        /// <exception cref="IO.Swagger.Client.ApiException">Thrown when fails to make API call</exception>
+        /// <param name="body">client model</param>
+        /// <returns>Task of ApiResponse (ModelClient)</returns>
+        System.Threading.Tasks.Task<ApiResponse<ModelClient>> TestSpecialTagsAsyncWithHttpInfo (ModelClient body);
+        #endregion Asynchronous Operations
+    }
+
+    /// <summary>
+    /// Represents a collection of functions to interact with the API endpoints
+    /// </summary>
+    public partial class AnotherFakeApi : IAnotherFakeApi
+    {
+        private IO.Swagger.Client.ExceptionFactory _exceptionFactory = (name, response) => null;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="AnotherFakeApi"/> class.
+        /// </summary>
+        /// <returns></returns>
+        public AnotherFakeApi(String basePath)
+        {
+            this.Configuration = new Configuration { BasePath = basePath };
+
+            ExceptionFactory = IO.Swagger.Client.Configuration.DefaultExceptionFactory;
+        }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="AnotherFakeApi"/> class
+        /// using Configuration object
+        /// </summary>
+        /// <param name="configuration">An instance of Configuration</param>
+        /// <returns></returns>
+        public AnotherFakeApi(Configuration configuration = null)
+        {
+            if (configuration == null) // use the default one in Configuration
+                this.Configuration = Configuration.Default;
+            else
+                this.Configuration = configuration;
+
+            ExceptionFactory = IO.Swagger.Client.Configuration.DefaultExceptionFactory;
+        }
+
+        /// <summary>
+        /// Gets the base path of the API client.
+        /// </summary>
+        /// <value>The base path</value>
+        public String GetBasePath()
+        {
+            return this.Configuration.ApiClient.RestClient.BaseUrl.ToString();
+        }
+
+        /// <summary>
+        /// Sets the base path of the API client.
+        /// </summary>
+        /// <value>The base path</value>
+        [Obsolete("SetBasePath is deprecated, please do 'Configuration.ApiClient = new ApiClient(\"http://new-path\")' instead.")]
+        public void SetBasePath(String basePath)
+        {
+            // do nothing
+        }
+
+        /// <summary>
+        /// Gets or sets the configuration object
+        /// </summary>
+        /// <value>An instance of the Configuration</value>
+        public Configuration Configuration {get; set;}
+
+        /// <summary>
+        /// Provides a factory method hook for the creation of exceptions.
+        /// </summary>
+        public IO.Swagger.Client.ExceptionFactory ExceptionFactory
+        {
+            get
+            {
+                if (_exceptionFactory != null && _exceptionFactory.GetInvocationList().Length > 1)
+                {
+                    throw new InvalidOperationException("Multicast delegate for ExceptionFactory is unsupported.");
+                }
+                return _exceptionFactory;
+            }
+            set { _exceptionFactory = value; }
+        }
+
+        /// <summary>
+        /// Gets the default header.
+        /// </summary>
+        /// <returns>Dictionary of HTTP header</returns>
+        [Obsolete("DefaultHeader is deprecated, please use Configuration.DefaultHeader instead.")]
+        public IDictionary<String, String> DefaultHeader()
+        {
+            return new ReadOnlyDictionary<string, string>(this.Configuration.DefaultHeader);
+        }
+
+        /// <summary>
+        /// Add default header.
+        /// </summary>
+        /// <param name="key">Header field name.</param>
+        /// <param name="value">Header field value.</param>
+        /// <returns></returns>
+        [Obsolete("AddDefaultHeader is deprecated, please use Configuration.AddDefaultHeader instead.")]
+        public void AddDefaultHeader(string key, string value)
+        {
+            this.Configuration.AddDefaultHeader(key, value);
+        }
+
+        /// <summary>
+        /// To test special tags To test special tags
+        /// </summary>
+        /// <exception cref="IO.Swagger.Client.ApiException">Thrown when fails to make API call</exception>
+        /// <param name="body">client model</param>
+        /// <returns>ModelClient</returns>
+        public ModelClient TestSpecialTags (ModelClient body)
+        {
+             ApiResponse<ModelClient> localVarResponse = TestSpecialTagsWithHttpInfo(body);
+             return localVarResponse.Data;
+        }
+
+        /// <summary>
+        /// To test special tags To test special tags
+        /// </summary>
+        /// <exception cref="IO.Swagger.Client.ApiException">Thrown when fails to make API call</exception>
+        /// <param name="body">client model</param>
+        /// <returns>ApiResponse of ModelClient</returns>
+        public ApiResponse< ModelClient > TestSpecialTagsWithHttpInfo (ModelClient body)
+        {
+            // verify the required parameter 'body' is set
+            if (body == null)
+                throw new ApiException(400, "Missing required parameter 'body' when calling AnotherFakeApi->TestSpecialTags");
+
+            var localVarPath = "/another-fake/dummy";
+            var localVarPathParams = new Dictionary<String, String>();
+            var localVarQueryParams = new List<KeyValuePair<String, String>>();
+            var localVarHeaderParams = new Dictionary<String, String>(Configuration.DefaultHeader);
+            var localVarFormParams = new Dictionary<String, String>();
+            var localVarFileParams = new Dictionary<String, FileParameter>();
+            Object localVarPostBody = null;
+
+            // to determine the Content-Type header
+            String[] localVarHttpContentTypes = new String[] {
+                "application/json"
+            };
+            String localVarHttpContentType = Configuration.ApiClient.SelectHeaderContentType(localVarHttpContentTypes);
+
+            // to determine the Accept header
+            String[] localVarHttpHeaderAccepts = new String[] {
+                "application/json"
+            };
+            String localVarHttpHeaderAccept = Configuration.ApiClient.SelectHeaderAccept(localVarHttpHeaderAccepts);
+            if (localVarHttpHeaderAccept != null)
+                localVarHeaderParams.Add("Accept", localVarHttpHeaderAccept);
+
+            if (body != null && body.GetType() != typeof(byte[]))
+            {
+                localVarPostBody = Configuration.ApiClient.Serialize(body); // http body (model) parameter
+            }
+            else
+            {
+                localVarPostBody = body; // byte array
+            }
+
+
+            // make the HTTP request
+            IRestResponse localVarResponse = (IRestResponse) Configuration.ApiClient.CallApi(localVarPath,
+                Method.PATCH, localVarQueryParams, localVarPostBody, localVarHeaderParams, localVarFormParams, localVarFileParams,
+                localVarPathParams, localVarHttpContentType);
+
+            int localVarStatusCode = (int) localVarResponse.StatusCode;
+
+            if (ExceptionFactory != null)
+            {
+                Exception exception = ExceptionFactory("TestSpecialTags", localVarResponse);
+                if (exception != null) throw exception;
+            }
+
+            return new ApiResponse<ModelClient>(localVarStatusCode,
+                localVarResponse.Headers.ToDictionary(x => x.Name, x => x.Value.ToString()),
+                (ModelClient) Configuration.ApiClient.Deserialize(localVarResponse, typeof(ModelClient)));
+        }
+
+        /// <summary>
+        /// To test special tags To test special tags
+        /// </summary>
+        /// <exception cref="IO.Swagger.Client.ApiException">Thrown when fails to make API call</exception>
+        /// <param name="body">client model</param>
+        /// <returns>Task of ModelClient</returns>
+        public async System.Threading.Tasks.Task<ModelClient> TestSpecialTagsAsync (ModelClient body)
+        {
+             ApiResponse<ModelClient> localVarResponse = await TestSpecialTagsAsyncWithHttpInfo(body);
+             return localVarResponse.Data;
+
+        }
+
+        /// <summary>
+        /// To test special tags To test special tags
+        /// </summary>
+        /// <exception cref="IO.Swagger.Client.ApiException">Thrown when fails to make API call</exception>
+        /// <param name="body">client model</param>
+        /// <returns>Task of ApiResponse (ModelClient)</returns>
+        public async System.Threading.Tasks.Task<ApiResponse<ModelClient>> TestSpecialTagsAsyncWithHttpInfo (ModelClient body)
+        {
+            // verify the required parameter 'body' is set
+            if (body == null)
+                throw new ApiException(400, "Missing required parameter 'body' when calling AnotherFakeApi->TestSpecialTags");
+
+            var localVarPath = "/another-fake/dummy";
+            var localVarPathParams = new Dictionary<String, String>();
+            var localVarQueryParams = new List<KeyValuePair<String, String>>();
+            var localVarHeaderParams = new Dictionary<String, String>(Configuration.DefaultHeader);
+            var localVarFormParams = new Dictionary<String, String>();
+            var localVarFileParams = new Dictionary<String, FileParameter>();
+            Object localVarPostBody = null;
+
+            // to determine the Content-Type header
+            String[] localVarHttpContentTypes = new String[] {
+                "application/json"
+            };
+            String localVarHttpContentType = Configuration.ApiClient.SelectHeaderContentType(localVarHttpContentTypes);
+
+            // to determine the Accept header
+            String[] localVarHttpHeaderAccepts = new String[] {
+                "application/json"
+            };
+            String localVarHttpHeaderAccept = Configuration.ApiClient.SelectHeaderAccept(localVarHttpHeaderAccepts);
+            if (localVarHttpHeaderAccept != null)
+                localVarHeaderParams.Add("Accept", localVarHttpHeaderAccept);
+
+            if (body != null && body.GetType() != typeof(byte[]))
+            {
+                localVarPostBody = Configuration.ApiClient.Serialize(body); // http body (model) parameter
+            }
+            else
+            {
+                localVarPostBody = body; // byte array
+            }
+
+
+            // make the HTTP request
+            IRestResponse localVarResponse = (IRestResponse) await Configuration.ApiClient.CallApiAsync(localVarPath,
+                Method.PATCH, localVarQueryParams, localVarPostBody, localVarHeaderParams, localVarFormParams, localVarFileParams,
+                localVarPathParams, localVarHttpContentType);
+
+            int localVarStatusCode = (int) localVarResponse.StatusCode;
+
+            if (ExceptionFactory != null)
+            {
+                Exception exception = ExceptionFactory("TestSpecialTags", localVarResponse);
+                if (exception != null) throw exception;
+            }
+
+            return new ApiResponse<ModelClient>(localVarStatusCode,
+                localVarResponse.Headers.ToDictionary(x => x.Name, x => x.Value.ToString()),
+                (ModelClient) Configuration.ApiClient.Deserialize(localVarResponse, typeof(ModelClient)));
+        }
+
+    }
+}

samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger/Api/FakeClassnameTags123Api.cs

@@ -0,0 +1,331 @@
+/* 
+ * Swagger Petstore
+ *
+ * This spec is mainly for testing Petstore server and contains fake endpoints, models. Please do not use this for any other purpose. Special characters: \" \\
+ *
+ * OpenAPI spec version: 1.0.0
+ * Contact: apiteam@swagger.io
+ * Generated by: https://github.com/swagger-api/swagger-codegen.git
+ */
+
+using System;
+using System.Collections.Generic;
+using System.Collections.ObjectModel;
+using System.Linq;
+using RestSharp;
+using IO.Swagger.Client;
+using IO.Swagger.Model;
+
+namespace IO.Swagger.Api
+{
+    /// <summary>
+    /// Represents a collection of functions to interact with the API endpoints
+    /// </summary>
+    public interface IFakeClassnameTags123Api : IApiAccessor
+    {
+        #region Synchronous Operations
+        /// <summary>
+        /// To test class name in snake case
+        /// </summary>
+        /// <remarks>
+        /// 
+        /// </remarks>
+        /// <exception cref="IO.Swagger.Client.ApiException">Thrown when fails to make API call</exception>
+        /// <param name="body">client model</param>
+        /// <returns>ModelClient</returns>
+        ModelClient TestClassname (ModelClient body);
+
+        /// <summary>
+        /// To test class name in snake case
+        /// </summary>
+        /// <remarks>
+        /// 
+        /// </remarks>
+        /// <exception cref="IO.Swagger.Client.ApiException">Thrown when fails to make API call</exception>
+        /// <param name="body">client model</param>
+        /// <returns>ApiResponse of ModelClient</returns>
+        ApiResponse<ModelClient> TestClassnameWithHttpInfo (ModelClient body);
+        #endregion Synchronous Operations
+        #region Asynchronous Operations
+        /// <summary>
+        /// To test class name in snake case
+        /// </summary>
+        /// <remarks>
+        /// 
+        /// </remarks>
+        /// <exception cref="IO.Swagger.Client.ApiException">Thrown when fails to make API call</exception>
+        /// <param name="body">client model</param>
+        /// <returns>Task of ModelClient</returns>
+        System.Threading.Tasks.Task<ModelClient> TestClassnameAsync (ModelClient body);
+
+        /// <summary>
+        /// To test class name in snake case
+        /// </summary>
+        /// <remarks>
+        /// 
+        /// </remarks>
+        /// <exception cref="IO.Swagger.Client.ApiException">Thrown when fails to make API call</exception>
+        /// <param name="body">client model</param>
+        /// <returns>Task of ApiResponse (ModelClient)</returns>
+        System.Threading.Tasks.Task<ApiResponse<ModelClient>> TestClassnameAsyncWithHttpInfo (ModelClient body);
+        #endregion Asynchronous Operations
+    }
+
+    /// <summary>
+    /// Represents a collection of functions to interact with the API endpoints
+    /// </summary>
+    public partial class FakeClassnameTags123Api : IFakeClassnameTags123Api
+    {
+        private IO.Swagger.Client.ExceptionFactory _exceptionFactory = (name, response) => null;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="FakeClassnameTags123Api"/> class.
+        /// </summary>
+        /// <returns></returns>
+        public FakeClassnameTags123Api(String basePath)
+        {
+            this.Configuration = new Configuration { BasePath = basePath };
+
+            ExceptionFactory = IO.Swagger.Client.Configuration.DefaultExceptionFactory;
+        }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="FakeClassnameTags123Api"/> class
+        /// using Configuration object
+        /// </summary>
+        /// <param name="configuration">An instance of Configuration</param>
+        /// <returns></returns>
+        public FakeClassnameTags123Api(Configuration configuration = null)
+        {
+            if (configuration == null) // use the default one in Configuration
+                this.Configuration = Configuration.Default;
+            else
+                this.Configuration = configuration;
+
+            ExceptionFactory = IO.Swagger.Client.Configuration.DefaultExceptionFactory;
+        }
+
+        /// <summary>
+        /// Gets the base path of the API client.
+        /// </summary>
+        /// <value>The base path</value>
+        public String GetBasePath()
+        {
+            return this.Configuration.ApiClient.RestClient.BaseUrl.ToString();
+        }
+
+        /// <summary>
+        /// Sets the base path of the API client.
+        /// </summary>
+        /// <value>The base path</value>
+        [Obsolete("SetBasePath is deprecated, please do 'Configuration.ApiClient = new ApiClient(\"http://new-path\")' instead.")]
+        public void SetBasePath(String basePath)
+        {
+            // do nothing
+        }
+
+        /// <summary>
+        /// Gets or sets the configuration object
+        /// </summary>
+        /// <value>An instance of the Configuration</value>
+        public Configuration Configuration {get; set;}
+
+        /// <summary>
+        /// Provides a factory method hook for the creation of exceptions.
+        /// </summary>
+        public IO.Swagger.Client.ExceptionFactory ExceptionFactory
+        {
+            get
+            {
+                if (_exceptionFactory != null && _exceptionFactory.GetInvocationList().Length > 1)
+                {
+                    throw new InvalidOperationException("Multicast delegate for ExceptionFactory is unsupported.");
+                }
+                return _exceptionFactory;
+            }
+            set { _exceptionFactory = value; }
+        }
+
+        /// <summary>
+        /// Gets the default header.
+        /// </summary>
+        /// <returns>Dictionary of HTTP header</returns>
+        [Obsolete("DefaultHeader is deprecated, please use Configuration.DefaultHeader instead.")]
+        public IDictionary<String, String> DefaultHeader()
+        {
+            return new ReadOnlyDictionary<string, string>(this.Configuration.DefaultHeader);
+        }
+
+        /// <summary>
+        /// Add default header.
+        /// </summary>
+        /// <param name="key">Header field name.</param>
+        /// <param name="value">Header field value.</param>
+        /// <returns></returns>
+        [Obsolete("AddDefaultHeader is deprecated, please use Configuration.AddDefaultHeader instead.")]
+        public void AddDefaultHeader(string key, string value)
+        {
+            this.Configuration.AddDefaultHeader(key, value);
+        }
+
+        /// <summary>
+        /// To test class name in snake case 
+        /// </summary>
+        /// <exception cref="IO.Swagger.Client.ApiException">Thrown when fails to make API call</exception>
+        /// <param name="body">client model</param>
+        /// <returns>ModelClient</returns>
+        public ModelClient TestClassname (ModelClient body)
+        {
+             ApiResponse<ModelClient> localVarResponse = TestClassnameWithHttpInfo(body);
+             return localVarResponse.Data;
+        }
+
+        /// <summary>
+        /// To test class name in snake case 
+        /// </summary>
+        /// <exception cref="IO.Swagger.Client.ApiException">Thrown when fails to make API call</exception>
+        /// <param name="body">client model</param>
+        /// <returns>ApiResponse of ModelClient</returns>
+        public ApiResponse< ModelClient > TestClassnameWithHttpInfo (ModelClient body)
+        {
+            // verify the required parameter 'body' is set
+            if (body == null)
+                throw new ApiException(400, "Missing required parameter 'body' when calling FakeClassnameTags123Api->TestClassname");
+
+            var localVarPath = "/fake_classname_test";
+            var localVarPathParams = new Dictionary<String, String>();
+            var localVarQueryParams = new List<KeyValuePair<String, String>>();
+            var localVarHeaderParams = new Dictionary<String, String>(Configuration.DefaultHeader);
+            var localVarFormParams = new Dictionary<String, String>();
+            var localVarFileParams = new Dictionary<String, FileParameter>();
+            Object localVarPostBody = null;
+
+            // to determine the Content-Type header
+            String[] localVarHttpContentTypes = new String[] {
+                "application/json"
+            };
+            String localVarHttpContentType = Configuration.ApiClient.SelectHeaderContentType(localVarHttpContentTypes);
+
+            // to determine the Accept header
+            String[] localVarHttpHeaderAccepts = new String[] {
+                "application/json"
+            };
+            String localVarHttpHeaderAccept = Configuration.ApiClient.SelectHeaderAccept(localVarHttpHeaderAccepts);
+            if (localVarHttpHeaderAccept != null)
+                localVarHeaderParams.Add("Accept", localVarHttpHeaderAccept);
+
+            if (body != null && body.GetType() != typeof(byte[]))
+            {
+                localVarPostBody = Configuration.ApiClient.Serialize(body); // http body (model) parameter
+            }
+            else
+            {
+                localVarPostBody = body; // byte array
+            }
+
+            // authentication (api_key_query) required
+            if (!String.IsNullOrEmpty(Configuration.GetApiKeyWithPrefix("api_key_query")))
+            {
+                localVarQueryParams.AddRange(Configuration.ApiClient.ParameterToKeyValuePairs("", "api_key_query", Configuration.GetApiKeyWithPrefix("api_key_query")));
+            }
+
+            // make the HTTP request
+            IRestResponse localVarResponse = (IRestResponse) Configuration.ApiClient.CallApi(localVarPath,
+                Method.PATCH, localVarQueryParams, localVarPostBody, localVarHeaderParams, localVarFormParams, localVarFileParams,
+                localVarPathParams, localVarHttpContentType);
+
+            int localVarStatusCode = (int) localVarResponse.StatusCode;
+
+            if (ExceptionFactory != null)
+            {
+                Exception exception = ExceptionFactory("TestClassname", localVarResponse);
+                if (exception != null) throw exception;
+            }
+
+            return new ApiResponse<ModelClient>(localVarStatusCode,
+                localVarResponse.Headers.ToDictionary(x => x.Name, x => x.Value.ToString()),
+                (ModelClient) Configuration.ApiClient.Deserialize(localVarResponse, typeof(ModelClient)));
+        }
+
+        /// <summary>
+        /// To test class name in snake case 
+        /// </summary>
+        /// <exception cref="IO.Swagger.Client.ApiException">Thrown when fails to make API call</exception>
+        /// <param name="body">client model</param>
+        /// <returns>Task of ModelClient</returns>
+        public async System.Threading.Tasks.Task<ModelClient> TestClassnameAsync (ModelClient body)
+        {
+             ApiResponse<ModelClient> localVarResponse = await TestClassnameAsyncWithHttpInfo(body);
+             return localVarResponse.Data;
+
+        }
+
+        /// <summary>
+        /// To test class name in snake case 
+        /// </summary>
+        /// <exception cref="IO.Swagger.Client.ApiException">Thrown when fails to make API call</exception>
+        /// <param name="body">client model</param>
+        /// <returns>Task of ApiResponse (ModelClient)</returns>
+        public async System.Threading.Tasks.Task<ApiResponse<ModelClient>> TestClassnameAsyncWithHttpInfo (ModelClient body)
+        {
+            // verify the required parameter 'body' is set
+            if (body == null)
+                throw new ApiException(400, "Missing required parameter 'body' when calling FakeClassnameTags123Api->TestClassname");
+
+            var localVarPath = "/fake_classname_test";
+            var localVarPathParams = new Dictionary<String, String>();
+            var localVarQueryParams = new List<KeyValuePair<String, String>>();
+            var localVarHeaderParams = new Dictionary<String, String>(Configuration.DefaultHeader);
+            var localVarFormParams = new Dictionary<String, String>();
+            var localVarFileParams = new Dictionary<String, FileParameter>();
+            Object localVarPostBody = null;
+
+            // to determine the Content-Type header
+            String[] localVarHttpContentTypes = new String[] {
+                "application/json"
+            };
+            String localVarHttpContentType = Configuration.ApiClient.SelectHeaderContentType(localVarHttpContentTypes);
+
+            // to determine the Accept header
+            String[] localVarHttpHeaderAccepts = new String[] {
+                "application/json"
+            };
+            String localVarHttpHeaderAccept = Configuration.ApiClient.SelectHeaderAccept(localVarHttpHeaderAccepts);
+            if (localVarHttpHeaderAccept != null)
+                localVarHeaderParams.Add("Accept", localVarHttpHeaderAccept);
+
+            if (body != null && body.GetType() != typeof(byte[]))
+            {
+                localVarPostBody = Configuration.ApiClient.Serialize(body); // http body (model) parameter
+            }
+            else
+            {
+                localVarPostBody = body; // byte array
+            }
+
+            // authentication (api_key_query) required
+            if (!String.IsNullOrEmpty(Configuration.GetApiKeyWithPrefix("api_key_query")))
+            {
+                localVarQueryParams.AddRange(Configuration.ApiClient.ParameterToKeyValuePairs("", "api_key_query", Configuration.GetApiKeyWithPrefix("api_key_query")));
+            }
+
+            // make the HTTP request
+            IRestResponse localVarResponse = (IRestResponse) await Configuration.ApiClient.CallApiAsync(localVarPath,
+                Method.PATCH, localVarQueryParams, localVarPostBody, localVarHeaderParams, localVarFormParams, localVarFileParams,
+                localVarPathParams, localVarHttpContentType);
+
+            int localVarStatusCode = (int) localVarResponse.StatusCode;
+
+            if (ExceptionFactory != null)
+            {
+                Exception exception = ExceptionFactory("TestClassname", localVarResponse);
+                if (exception != null) throw exception;
+            }
+
+            return new ApiResponse<ModelClient>(localVarStatusCode,
+                localVarResponse.Headers.ToDictionary(x => x.Name, x => x.Value.ToString()),
+                (ModelClient) Configuration.ApiClient.Deserialize(localVarResponse, typeof(ModelClient)));
+        }
+
+    }
+}

samples/client/petstore/csharp/SwaggerClient/src/IO.Swagger/Client/ApiClient.cs

@@ -139,14 +139,7 @@ namespace IO.Swagger.Client
 
             if (postBody != null) // http body (model or byte[]) parameter
             {
-                if (postBody.GetType() == typeof(String))
-                {
-                    request.AddParameter("application/json", postBody, ParameterType.RequestBody);
-                }
-                else if (postBody.GetType() == typeof(byte[]))
-                {
-                    request.AddParameter(contentType, postBody, ParameterType.RequestBody);
-                }
+				request.AddParameter(contentType, postBody, ParameterType.RequestBody);
             }
 
             return request;
@@ -351,9 +344,25 @@ namespace IO.Swagger.Client
             }
         }
 
+        /// <summary>
+        ///Check if the given MIME is a JSON MIME.
+        ///JSON MIME examples:
+        ///	   application/json
+        ///    application/json; charset=UTF8
+        ///    APPLICATION/JSON
+        ///    application/vnd.company+json
+        /// </summary>
+        /// <param name="mime">MIME</param>
+        /// <returns>Returns True if MIME type is json.</returns>		
+        public bool IsJsonMime(String mime)
+        {
+            var jsonRegex = new Regex("(?i)^(application/json|[^;/ \t]+/[^;/ \t]+[+]json)[ \t]*(;.*)?$");
+            return mime != null && (jsonRegex.IsMatch(mime) || mime.Equals("application/json-patch+json", StringComparison.InvariantCultureIgnoreCase));
+        }	
+
         /// <summary>
         /// Select the Content-Type header's value from the given content-type array:
-        /// if JSON exists in the given array, use it;
+        /// if JSON type exists in the given array, use it;
         /// otherwise use the first one defined in 'consumes'
         /// </summary>
         /// <param name="contentTypes">The Content-Type array to select from.</param>
@@ -361,11 +370,14 @@ namespace IO.Swagger.Client
         public String SelectHeaderContentType(String[] contentTypes)
         {
             if (contentTypes.Length == 0)
-                return null;
-
-            if (contentTypes.Contains("application/json", StringComparer.OrdinalIgnoreCase))
                 return "application/json";
 
+            foreach (var contentType in contentTypes)
+            {
+                if (IsJsonMime(contentType))
+                    return contentType;
+            }
+
             return contentTypes[0]; // use the first content type specified in 'consumes'
         }