diff --git a/modules/swagger-codegen/src/main/resources/csharp/api.mustache b/modules/swagger-codegen/src/main/resources/csharp/api.mustache
index f7cc79c5255c..ee3f326c746b 100644
--- a/modules/swagger-codegen/src/main/resources/csharp/api.mustache
+++ b/modules/swagger-codegen/src/main/resources/csharp/api.mustache
@@ -10,12 +10,12 @@ namespace {{package}} {
   {{#operations}}
   public class {{classname}} {
     string basePath;
-    protected RestClient restClient;
+    public ApiInvoker apiClient {get; set;}
 
     public {{classname}}(String basePath = "{{basePath}}")
     {
       this.basePath = basePath;
-      this.restClient = new RestClient(basePath);
+      this.apiClient = new ApiInvoker(basePath);
     }
 
     /// <summary>
@@ -45,37 +45,38 @@ namespace {{package}} {
     /// <returns>{{#returnType}}{{{returnType}}}{{/returnType}}</returns>
     public {{#returnType}}{{{returnType}}}{{/returnType}}{{^returnType}}void{{/returnType}} {{nickname}} ({{#allParams}}{{{dataType}}} {{paramName}}{{#hasMore}}, {{/hasMore}}{{/allParams}}) {
 
-      var _request = new RestRequest("{{path}}", Method.{{httpMethod}});
-
       {{#allParams}}{{#required}}
       // verify the required parameter '{{paramName}}' is set
       if ({{paramName}} == null) throw new ApiException(400, "Missing required parameter '{{paramName}}' when calling {{nickname}}");
       {{/required}}{{/allParams}}
 
-      // add default header, if any
-      foreach(KeyValuePair<string, string> defaultHeader in ApiInvoker.GetDefaultHeader())
-      {
-        _request.AddHeader(defaultHeader.Key, defaultHeader.Value);
-      }
-
-      _request.AddUrlSegment("format", "json"); // set format to json by default
-      {{#pathParams}}_request.AddUrlSegment("{{baseName}}", ApiInvoker.ParameterToString({{{paramName}}})); // path (url segment) parameter
+      var path = "{{path}}";
+      path = path.Replace("{format}", "json");
+      {{#pathParams}}path = path.Replace("{" + "{{baseName}}" + "}", apiClient.ParameterToString({{{paramName}}}));
       {{/pathParams}}
-      {{#queryParams}} if ({{paramName}} != null) _request.AddParameter("{{baseName}}", ApiInvoker.ParameterToString({{paramName}})); // query parameter
+
+      var queryParams = new Dictionary<String, String>();
+      var headerParams = new Dictionary<String, String>();
+      var formParams = new Dictionary<String, String>();
+      var fileParams = new Dictionary<String, String>();
+      String postBody = null;
+
+      {{#queryParams}} if ({{paramName}} != null) queryParams.Add("{{baseName}}", apiClient.ParameterToString({{paramName}})); // query parameter
       {{/queryParams}}
-      {{#headerParams}} if ({{paramName}} != null) _request.AddHeader("{{baseName}}", ApiInvoker.ParameterToString({{paramName}})); // header parameter
+      {{#headerParams}} if ({{paramName}} != null) headerParams.Add("{{baseName}}", apiClient.ParameterToString({{paramName}})); // header parameter
       {{/headerParams}}
-      {{#formParams}}if ({{paramName}} != null) {{#isFile}}_request.AddFile("{{baseName}}", {{paramName}});{{/isFile}}{{^isFile}}_request.AddParameter("{{baseName}}", ApiInvoker.ParameterToString({{paramName}})); // form parameter{{/isFile}}
+      {{#formParams}}if ({{paramName}} != null) {{#isFile}}fileParams.Add("{{baseName}}", {{paramName}});{{/isFile}}{{^isFile}}formParams.Add("{{baseName}}", apiClient.ParameterToString({{paramName}})); // form parameter{{/isFile}}
       {{/formParams}}
-      {{#bodyParam}}_request.AddParameter("application/json", ApiInvoker.Serialize({{paramName}}), ParameterType.RequestBody); // http body (model) parameter
+      {{#bodyParam}}postBody = apiClient.Serialize({{paramName}}); // http body (model) parameter
       {{/bodyParam}}
 
       // make the HTTP request
-      IRestResponse response = restClient.Execute(_request);
+      IRestResponse response = (IRestResponse) apiClient.CallApi("{{path}}", Method.{{httpMethod}}, queryParams, postBody, headerParams, formParams, fileParams);
+
       if (((int)response.StatusCode) >= 400) {
         throw new ApiException ((int)response.StatusCode, "Error calling {{nickname}}: " + response.Content);
       }
-      {{#returnType}}return ({{{returnType}}}) ApiInvoker.Deserialize(response.Content, typeof({{{returnType}}}));{{/returnType}}{{^returnType}}
+      {{#returnType}}return ({{{returnType}}}) apiClient.Deserialize(response.Content, typeof({{{returnType}}}));{{/returnType}}{{^returnType}}
       return;{{/returnType}}
     }
     {{/operation}}
diff --git a/modules/swagger-codegen/src/main/resources/csharp/apiInvoker.mustache b/modules/swagger-codegen/src/main/resources/csharp/apiInvoker.mustache
index 9760e44d81a6..01406a8add08 100644
--- a/modules/swagger-codegen/src/main/resources/csharp/apiInvoker.mustache
+++ b/modules/swagger-codegen/src/main/resources/csharp/apiInvoker.mustache
@@ -5,10 +5,54 @@ using System.Linq;
 using System.Net;
 using System.Text;
 using Newtonsoft.Json;
+using RestSharp;
 
 namespace {{invokerPackage}} {
   public class ApiInvoker {
-    private static Dictionary<String, String> defaultHeaderMap = new Dictionary<String, String>();
+    public ApiInvoker() {
+      this.basePath = "{{basePath}}";
+    }
+
+    public ApiInvoker(String basePath) {
+      this.basePath = basePath;
+    }
+
+    public string basePath { get; set; }
+    public RestClient restClient { get; set; }
+    private Dictionary<String, String> defaultHeaderMap = new Dictionary<String, String>();
+
+    public Object CallApi(String Path, RestSharp.Method Method, Dictionary<String, String> QueryParams, String PostBody, 
+      Dictionary<String, String> HeaderParams, Dictionary<String, String> FormParams, Dictionary<String, String> FileParams) {
+
+      var request = new RestRequest(Path, Method);
+
+      // add default header, if any
+      foreach(KeyValuePair<string, string> defaultHeader in this.defaultHeaderMap)
+        request.AddHeader(defaultHeader.Key, defaultHeader.Value);
+
+      // add header parameter, if any
+      foreach(KeyValuePair<string, string> param in HeaderParams)
+        request.AddHeader(param.Key, param.Value);
+     
+      // add query parameter, if any
+      foreach(KeyValuePair<string, string> param in QueryParams)
+        request.AddUrlSegment(param.Key, param.Value);
+
+      // add form parameter, if any
+      foreach(KeyValuePair<string, string> param in FormParams)
+        request.AddParameter(param.Key, param.Value);
+
+      // add file parameter, if any
+      foreach(KeyValuePair<string, string> param in FormParams)
+        request.AddFile(param.Key, param.Value);
+
+      if (PostBody == null) {
+        request.AddParameter("application/json", PostBody, ParameterType.RequestBody); // http body (model) parameter
+      }
+
+      return (Object)restClient.Execute(request);
+
+    }
 
     /// <summary>
     /// Add default header
@@ -16,7 +60,7 @@ namespace {{invokerPackage}} {
     /// <param name="key">  Header field name
     /// <param name="value"> Header field value
     /// <returns></returns>
-    public static void AddDefaultHeader(string key, string value) {
+    public void AddDefaultHeader(string key, string value) {
        defaultHeaderMap.Add(key, value);
     }
 
@@ -24,7 +68,7 @@ namespace {{invokerPackage}} {
     /// Get default header
     /// </summary>
     /// <returns>Dictionary of default header</returns>
-    public static Dictionary<String, String> GetDefaultHeader() {
+    public Dictionary<String, String> GetDefaultHeader() {
        return defaultHeaderMap;
     }
 
@@ -33,7 +77,7 @@ namespace {{invokerPackage}} {
     /// </summary>
     /// <param name="str"> String to be escaped
     /// <returns>Escaped string</returns>
-    public static string EscapeString(string str) {
+    public string EscapeString(string str) {
       return str;
     }
 
@@ -42,7 +86,7 @@ namespace {{invokerPackage}} {
     /// </summary>
     /// <param name="obj"> The parameter (header, path, query, form)
     /// <returns>Formatted string</returns>
-    public static string ParameterToString(object obj)
+    public string ParameterToString(object obj)
     {
       return (obj is DateTime) ? ((DateTime)obj).ToString ("u") : Convert.ToString (obj);
     }
@@ -53,7 +97,7 @@ namespace {{invokerPackage}} {
     /// <param name="json"> JSON string
     /// <param name="type"> Object type
     /// <returns>Object representation of the JSON string</returns>
-    public static object Deserialize(string content, Type type) {
+    public object Deserialize(string content, Type type) {
       if (type.GetType() == typeof(Object))
         return (Object)content;
 
@@ -71,7 +115,7 @@ namespace {{invokerPackage}} {
     /// </summary>
     /// <param name="obj"> Object 
     /// <returns>JSON string</returns>
-    public static string Serialize(object obj) {
+    public string Serialize(object obj) {
       try
       {
           return obj != null ? JsonConvert.SerializeObject(obj) : null;
diff --git a/samples/client/petstore/csharp/src/main/csharp/io/swagger/Api/PetApi.cs b/samples/client/petstore/csharp/src/main/csharp/io/swagger/Api/PetApi.cs
index 6a39ce7ba753..054cb1bc204b 100644
--- a/samples/client/petstore/csharp/src/main/csharp/io/swagger/Api/PetApi.cs
+++ b/samples/client/petstore/csharp/src/main/csharp/io/swagger/Api/PetApi.cs
@@ -8,12 +8,12 @@ namespace IO.Swagger.Api {
   
   public class PetApi {
     string basePath;
-    protected RestClient restClient;
+    public ApiInvoker apiClient {get; set;}
 
     public PetApi(String basePath = "http://petstore.swagger.io/v2")
     {
       this.basePath = basePath;
-      this.restClient = new RestClient(basePath);
+      this.apiClient = new ApiInvoker(basePath);
     }
 
     /// <summary>
@@ -42,26 +42,27 @@ namespace IO.Swagger.Api {
     /// <returns></returns>
     public void UpdatePet (Pet Body) {
 
-      var _request = new RestRequest("/pet", Method.PUT);
-
       
 
-      // add default header, if any
-      foreach(KeyValuePair<string, string> defaultHeader in ApiInvoker.GetDefaultHeader())
-      {
-        _request.AddHeader(defaultHeader.Key, defaultHeader.Value);
-      }
+      var path = "/pet";
+      path = path.Replace("{format}", "json");
+      
+
+      var queryParams = new Dictionary<String, String>();
+      var headerParams = new Dictionary<String, String>();
+      var formParams = new Dictionary<String, String>();
+      var fileParams = new Dictionary<String, String>();
+      String postBody = null;
 
-      _request.AddUrlSegment("format", "json"); // set format to json by default
       
       
       
-      
-      _request.AddParameter("application/json", ApiInvoker.Serialize(Body), ParameterType.RequestBody); // http body (model) parameter
+      postBody = apiClient.Serialize(Body); // http body (model) parameter
       
 
       // make the HTTP request
-      IRestResponse response = restClient.Execute(_request);
+      IRestResponse response = (IRestResponse) apiClient.CallApi("/pet", Method.PUT, queryParams, postBody, headerParams, formParams, fileParams);
+
       if (((int)response.StatusCode) >= 400) {
         throw new ApiException ((int)response.StatusCode, "Error calling UpdatePet: " + response.Content);
       }
@@ -77,26 +78,27 @@ namespace IO.Swagger.Api {
     /// <returns></returns>
     public void AddPet (Pet Body) {
 
-      var _request = new RestRequest("/pet", Method.POST);
-
       
 
-      // add default header, if any
-      foreach(KeyValuePair<string, string> defaultHeader in ApiInvoker.GetDefaultHeader())
-      {
-        _request.AddHeader(defaultHeader.Key, defaultHeader.Value);
-      }
+      var path = "/pet";
+      path = path.Replace("{format}", "json");
+      
+
+      var queryParams = new Dictionary<String, String>();
+      var headerParams = new Dictionary<String, String>();
+      var formParams = new Dictionary<String, String>();
+      var fileParams = new Dictionary<String, String>();
+      String postBody = null;
 
-      _request.AddUrlSegment("format", "json"); // set format to json by default
       
       
       
-      
-      _request.AddParameter("application/json", ApiInvoker.Serialize(Body), ParameterType.RequestBody); // http body (model) parameter
+      postBody = apiClient.Serialize(Body); // http body (model) parameter
       
 
       // make the HTTP request
-      IRestResponse response = restClient.Execute(_request);
+      IRestResponse response = (IRestResponse) apiClient.CallApi("/pet", Method.POST, queryParams, postBody, headerParams, formParams, fileParams);
+
       if (((int)response.StatusCode) >= 400) {
         throw new ApiException ((int)response.StatusCode, "Error calling AddPet: " + response.Content);
       }
@@ -112,30 +114,31 @@ namespace IO.Swagger.Api {
     /// <returns>List<Pet></returns>
     public List<Pet> FindPetsByStatus (List<string> Status) {
 
-      var _request = new RestRequest("/pet/findByStatus", Method.GET);
-
       
 
-      // add default header, if any
-      foreach(KeyValuePair<string, string> defaultHeader in ApiInvoker.GetDefaultHeader())
-      {
-        _request.AddHeader(defaultHeader.Key, defaultHeader.Value);
-      }
-
-      _request.AddUrlSegment("format", "json"); // set format to json by default
+      var path = "/pet/findByStatus";
+      path = path.Replace("{format}", "json");
       
-       if (Status != null) _request.AddParameter("status", ApiInvoker.ParameterToString(Status)); // query parameter
+
+      var queryParams = new Dictionary<String, String>();
+      var headerParams = new Dictionary<String, String>();
+      var formParams = new Dictionary<String, String>();
+      var fileParams = new Dictionary<String, String>();
+      String postBody = null;
+
+       if (Status != null) queryParams.Add("status", apiClient.ParameterToString(Status)); // query parameter
       
       
       
       
 
       // make the HTTP request
-      IRestResponse response = restClient.Execute(_request);
+      IRestResponse response = (IRestResponse) apiClient.CallApi("/pet/findByStatus", Method.GET, queryParams, postBody, headerParams, formParams, fileParams);
+
       if (((int)response.StatusCode) >= 400) {
         throw new ApiException ((int)response.StatusCode, "Error calling FindPetsByStatus: " + response.Content);
       }
-      return (List<Pet>) ApiInvoker.Deserialize(response.Content, typeof(List<Pet>));
+      return (List<Pet>) apiClient.Deserialize(response.Content, typeof(List<Pet>));
     }
     
     
@@ -146,30 +149,31 @@ namespace IO.Swagger.Api {
     /// <returns>List<Pet></returns>
     public List<Pet> FindPetsByTags (List<string> Tags) {
 
-      var _request = new RestRequest("/pet/findByTags", Method.GET);
-
       
 
-      // add default header, if any
-      foreach(KeyValuePair<string, string> defaultHeader in ApiInvoker.GetDefaultHeader())
-      {
-        _request.AddHeader(defaultHeader.Key, defaultHeader.Value);
-      }
-
-      _request.AddUrlSegment("format", "json"); // set format to json by default
+      var path = "/pet/findByTags";
+      path = path.Replace("{format}", "json");
       
-       if (Tags != null) _request.AddParameter("tags", ApiInvoker.ParameterToString(Tags)); // query parameter
+
+      var queryParams = new Dictionary<String, String>();
+      var headerParams = new Dictionary<String, String>();
+      var formParams = new Dictionary<String, String>();
+      var fileParams = new Dictionary<String, String>();
+      String postBody = null;
+
+       if (Tags != null) queryParams.Add("tags", apiClient.ParameterToString(Tags)); // query parameter
       
       
       
       
 
       // make the HTTP request
-      IRestResponse response = restClient.Execute(_request);
+      IRestResponse response = (IRestResponse) apiClient.CallApi("/pet/findByTags", Method.GET, queryParams, postBody, headerParams, formParams, fileParams);
+
       if (((int)response.StatusCode) >= 400) {
         throw new ApiException ((int)response.StatusCode, "Error calling FindPetsByTags: " + response.Content);
       }
-      return (List<Pet>) ApiInvoker.Deserialize(response.Content, typeof(List<Pet>));
+      return (List<Pet>) apiClient.Deserialize(response.Content, typeof(List<Pet>));
     }
     
     
@@ -180,33 +184,34 @@ namespace IO.Swagger.Api {
     /// <returns>Pet</returns>
     public Pet GetPetById (long? PetId) {
 
-      var _request = new RestRequest("/pet/{petId}", Method.GET);
-
       
       // verify the required parameter 'PetId' is set
       if (PetId == null) throw new ApiException(400, "Missing required parameter 'PetId' when calling GetPetById");
       
 
-      // add default header, if any
-      foreach(KeyValuePair<string, string> defaultHeader in ApiInvoker.GetDefaultHeader())
-      {
-        _request.AddHeader(defaultHeader.Key, defaultHeader.Value);
-      }
-
-      _request.AddUrlSegment("format", "json"); // set format to json by default
-      _request.AddUrlSegment("petId", ApiInvoker.ParameterToString(PetId)); // path (url segment) parameter
+      var path = "/pet/{petId}";
+      path = path.Replace("{format}", "json");
+      path = path.Replace("{" + "petId" + "}", apiClient.ParameterToString(PetId));
       
+
+      var queryParams = new Dictionary<String, String>();
+      var headerParams = new Dictionary<String, String>();
+      var formParams = new Dictionary<String, String>();
+      var fileParams = new Dictionary<String, String>();
+      String postBody = null;
+
       
       
       
       
 
       // make the HTTP request
-      IRestResponse response = restClient.Execute(_request);
+      IRestResponse response = (IRestResponse) apiClient.CallApi("/pet/{petId}", Method.GET, queryParams, postBody, headerParams, formParams, fileParams);
+
       if (((int)response.StatusCode) >= 400) {
         throw new ApiException ((int)response.StatusCode, "Error calling GetPetById: " + response.Content);
       }
-      return (Pet) ApiInvoker.Deserialize(response.Content, typeof(Pet));
+      return (Pet) apiClient.Deserialize(response.Content, typeof(Pet));
     }
     
     
@@ -219,31 +224,32 @@ namespace IO.Swagger.Api {
     /// <returns></returns>
     public void UpdatePetWithForm (string PetId, string Name, string Status) {
 
-      var _request = new RestRequest("/pet/{petId}", Method.POST);
-
       
       // verify the required parameter 'PetId' is set
       if (PetId == null) throw new ApiException(400, "Missing required parameter 'PetId' when calling UpdatePetWithForm");
       
 
-      // add default header, if any
-      foreach(KeyValuePair<string, string> defaultHeader in ApiInvoker.GetDefaultHeader())
-      {
-        _request.AddHeader(defaultHeader.Key, defaultHeader.Value);
-      }
+      var path = "/pet/{petId}";
+      path = path.Replace("{format}", "json");
+      path = path.Replace("{" + "petId" + "}", apiClient.ParameterToString(PetId));
+      
+
+      var queryParams = new Dictionary<String, String>();
+      var headerParams = new Dictionary<String, String>();
+      var formParams = new Dictionary<String, String>();
+      var fileParams = new Dictionary<String, String>();
+      String postBody = null;
 
-      _request.AddUrlSegment("format", "json"); // set format to json by default
-      _request.AddUrlSegment("petId", ApiInvoker.ParameterToString(PetId)); // path (url segment) parameter
       
       
-      
-      if (Name != null) _request.AddParameter("name", ApiInvoker.ParameterToString(Name)); // form parameter
-      if (Status != null) _request.AddParameter("status", ApiInvoker.ParameterToString(Status)); // form parameter
+      if (Name != null) formParams.Add("name", apiClient.ParameterToString(Name)); // form parameter
+      if (Status != null) formParams.Add("status", apiClient.ParameterToString(Status)); // form parameter
       
       
 
       // make the HTTP request
-      IRestResponse response = restClient.Execute(_request);
+      IRestResponse response = (IRestResponse) apiClient.CallApi("/pet/{petId}", Method.POST, queryParams, postBody, headerParams, formParams, fileParams);
+
       if (((int)response.StatusCode) >= 400) {
         throw new ApiException ((int)response.StatusCode, "Error calling UpdatePetWithForm: " + response.Content);
       }
@@ -260,30 +266,31 @@ namespace IO.Swagger.Api {
     /// <returns></returns>
     public void DeletePet (string ApiKey, long? PetId) {
 
-      var _request = new RestRequest("/pet/{petId}", Method.DELETE);
-
       
       // verify the required parameter 'PetId' is set
       if (PetId == null) throw new ApiException(400, "Missing required parameter 'PetId' when calling DeletePet");
       
 
-      // add default header, if any
-      foreach(KeyValuePair<string, string> defaultHeader in ApiInvoker.GetDefaultHeader())
-      {
-        _request.AddHeader(defaultHeader.Key, defaultHeader.Value);
-      }
+      var path = "/pet/{petId}";
+      path = path.Replace("{format}", "json");
+      path = path.Replace("{" + "petId" + "}", apiClient.ParameterToString(PetId));
+      
+
+      var queryParams = new Dictionary<String, String>();
+      var headerParams = new Dictionary<String, String>();
+      var formParams = new Dictionary<String, String>();
+      var fileParams = new Dictionary<String, String>();
+      String postBody = null;
 
-      _request.AddUrlSegment("format", "json"); // set format to json by default
-      _request.AddUrlSegment("petId", ApiInvoker.ParameterToString(PetId)); // path (url segment) parameter
       
-      
-       if (ApiKey != null) _request.AddHeader("api_key", ApiInvoker.ParameterToString(ApiKey)); // header parameter
+       if (ApiKey != null) headerParams.Add("api_key", apiClient.ParameterToString(ApiKey)); // header parameter
       
       
       
 
       // make the HTTP request
-      IRestResponse response = restClient.Execute(_request);
+      IRestResponse response = (IRestResponse) apiClient.CallApi("/pet/{petId}", Method.DELETE, queryParams, postBody, headerParams, formParams, fileParams);
+
       if (((int)response.StatusCode) >= 400) {
         throw new ApiException ((int)response.StatusCode, "Error calling DeletePet: " + response.Content);
       }
@@ -301,31 +308,32 @@ namespace IO.Swagger.Api {
     /// <returns></returns>
     public void UploadFile (long? PetId, string AdditionalMetadata, string File) {
 
-      var _request = new RestRequest("/pet/{petId}/uploadImage", Method.POST);
-
       
       // verify the required parameter 'PetId' is set
       if (PetId == null) throw new ApiException(400, "Missing required parameter 'PetId' when calling UploadFile");
       
 
-      // add default header, if any
-      foreach(KeyValuePair<string, string> defaultHeader in ApiInvoker.GetDefaultHeader())
-      {
-        _request.AddHeader(defaultHeader.Key, defaultHeader.Value);
-      }
+      var path = "/pet/{petId}/uploadImage";
+      path = path.Replace("{format}", "json");
+      path = path.Replace("{" + "petId" + "}", apiClient.ParameterToString(PetId));
+      
+
+      var queryParams = new Dictionary<String, String>();
+      var headerParams = new Dictionary<String, String>();
+      var formParams = new Dictionary<String, String>();
+      var fileParams = new Dictionary<String, String>();
+      String postBody = null;
 
-      _request.AddUrlSegment("format", "json"); // set format to json by default
-      _request.AddUrlSegment("petId", ApiInvoker.ParameterToString(PetId)); // path (url segment) parameter
       
       
-      
-      if (AdditionalMetadata != null) _request.AddParameter("additionalMetadata", ApiInvoker.ParameterToString(AdditionalMetadata)); // form parameter
-      if (File != null) _request.AddFile("file", File);
+      if (AdditionalMetadata != null) formParams.Add("additionalMetadata", apiClient.ParameterToString(AdditionalMetadata)); // form parameter
+      if (File != null) fileParams.Add("file", File);
       
       
 
       // make the HTTP request
-      IRestResponse response = restClient.Execute(_request);
+      IRestResponse response = (IRestResponse) apiClient.CallApi("/pet/{petId}/uploadImage", Method.POST, queryParams, postBody, headerParams, formParams, fileParams);
+
       if (((int)response.StatusCode) >= 400) {
         throw new ApiException ((int)response.StatusCode, "Error calling UploadFile: " + response.Content);
       }
diff --git a/samples/client/petstore/csharp/src/main/csharp/io/swagger/Api/StoreApi.cs b/samples/client/petstore/csharp/src/main/csharp/io/swagger/Api/StoreApi.cs
index 5b4236c7a777..9d10a095c447 100644
--- a/samples/client/petstore/csharp/src/main/csharp/io/swagger/Api/StoreApi.cs
+++ b/samples/client/petstore/csharp/src/main/csharp/io/swagger/Api/StoreApi.cs
@@ -8,12 +8,12 @@ namespace IO.Swagger.Api {
   
   public class StoreApi {
     string basePath;
-    protected RestClient restClient;
+    public ApiInvoker apiClient {get; set;}
 
     public StoreApi(String basePath = "http://petstore.swagger.io/v2")
     {
       this.basePath = basePath;
-      this.restClient = new RestClient(basePath);
+      this.apiClient = new ApiInvoker(basePath);
     }
 
     /// <summary>
@@ -41,29 +41,30 @@ namespace IO.Swagger.Api {
     /// <returns>Dictionary<String, int?></returns>
     public Dictionary<String, int?> GetInventory () {
 
-      var _request = new RestRequest("/store/inventory", Method.GET);
-
       
 
-      // add default header, if any
-      foreach(KeyValuePair<string, string> defaultHeader in ApiInvoker.GetDefaultHeader())
-      {
-        _request.AddHeader(defaultHeader.Key, defaultHeader.Value);
-      }
-
-      _request.AddUrlSegment("format", "json"); // set format to json by default
+      var path = "/store/inventory";
+      path = path.Replace("{format}", "json");
       
+
+      var queryParams = new Dictionary<String, String>();
+      var headerParams = new Dictionary<String, String>();
+      var formParams = new Dictionary<String, String>();
+      var fileParams = new Dictionary<String, String>();
+      String postBody = null;
+
       
       
       
       
 
       // make the HTTP request
-      IRestResponse response = restClient.Execute(_request);
+      IRestResponse response = (IRestResponse) apiClient.CallApi("/store/inventory", Method.GET, queryParams, postBody, headerParams, formParams, fileParams);
+
       if (((int)response.StatusCode) >= 400) {
         throw new ApiException ((int)response.StatusCode, "Error calling GetInventory: " + response.Content);
       }
-      return (Dictionary<String, int?>) ApiInvoker.Deserialize(response.Content, typeof(Dictionary<String, int?>));
+      return (Dictionary<String, int?>) apiClient.Deserialize(response.Content, typeof(Dictionary<String, int?>));
     }
     
     
@@ -74,30 +75,31 @@ namespace IO.Swagger.Api {
     /// <returns>Order</returns>
     public Order PlaceOrder (Order Body) {
 
-      var _request = new RestRequest("/store/order", Method.POST);
-
       
 
-      // add default header, if any
-      foreach(KeyValuePair<string, string> defaultHeader in ApiInvoker.GetDefaultHeader())
-      {
-        _request.AddHeader(defaultHeader.Key, defaultHeader.Value);
-      }
+      var path = "/store/order";
+      path = path.Replace("{format}", "json");
+      
+
+      var queryParams = new Dictionary<String, String>();
+      var headerParams = new Dictionary<String, String>();
+      var formParams = new Dictionary<String, String>();
+      var fileParams = new Dictionary<String, String>();
+      String postBody = null;
 
-      _request.AddUrlSegment("format", "json"); // set format to json by default
       
       
       
-      
-      _request.AddParameter("application/json", ApiInvoker.Serialize(Body), ParameterType.RequestBody); // http body (model) parameter
+      postBody = apiClient.Serialize(Body); // http body (model) parameter
       
 
       // make the HTTP request
-      IRestResponse response = restClient.Execute(_request);
+      IRestResponse response = (IRestResponse) apiClient.CallApi("/store/order", Method.POST, queryParams, postBody, headerParams, formParams, fileParams);
+
       if (((int)response.StatusCode) >= 400) {
         throw new ApiException ((int)response.StatusCode, "Error calling PlaceOrder: " + response.Content);
       }
-      return (Order) ApiInvoker.Deserialize(response.Content, typeof(Order));
+      return (Order) apiClient.Deserialize(response.Content, typeof(Order));
     }
     
     
@@ -108,33 +110,34 @@ namespace IO.Swagger.Api {
     /// <returns>Order</returns>
     public Order GetOrderById (string OrderId) {
 
-      var _request = new RestRequest("/store/order/{orderId}", Method.GET);
-
       
       // verify the required parameter 'OrderId' is set
       if (OrderId == null) throw new ApiException(400, "Missing required parameter 'OrderId' when calling GetOrderById");
       
 
-      // add default header, if any
-      foreach(KeyValuePair<string, string> defaultHeader in ApiInvoker.GetDefaultHeader())
-      {
-        _request.AddHeader(defaultHeader.Key, defaultHeader.Value);
-      }
-
-      _request.AddUrlSegment("format", "json"); // set format to json by default
-      _request.AddUrlSegment("orderId", ApiInvoker.ParameterToString(OrderId)); // path (url segment) parameter
+      var path = "/store/order/{orderId}";
+      path = path.Replace("{format}", "json");
+      path = path.Replace("{" + "orderId" + "}", apiClient.ParameterToString(OrderId));
       
+
+      var queryParams = new Dictionary<String, String>();
+      var headerParams = new Dictionary<String, String>();
+      var formParams = new Dictionary<String, String>();
+      var fileParams = new Dictionary<String, String>();
+      String postBody = null;
+
       
       
       
       
 
       // make the HTTP request
-      IRestResponse response = restClient.Execute(_request);
+      IRestResponse response = (IRestResponse) apiClient.CallApi("/store/order/{orderId}", Method.GET, queryParams, postBody, headerParams, formParams, fileParams);
+
       if (((int)response.StatusCode) >= 400) {
         throw new ApiException ((int)response.StatusCode, "Error calling GetOrderById: " + response.Content);
       }
-      return (Order) ApiInvoker.Deserialize(response.Content, typeof(Order));
+      return (Order) apiClient.Deserialize(response.Content, typeof(Order));
     }
     
     
@@ -145,29 +148,30 @@ namespace IO.Swagger.Api {
     /// <returns></returns>
     public void DeleteOrder (string OrderId) {
 
-      var _request = new RestRequest("/store/order/{orderId}", Method.DELETE);
-
       
       // verify the required parameter 'OrderId' is set
       if (OrderId == null) throw new ApiException(400, "Missing required parameter 'OrderId' when calling DeleteOrder");
       
 
-      // add default header, if any
-      foreach(KeyValuePair<string, string> defaultHeader in ApiInvoker.GetDefaultHeader())
-      {
-        _request.AddHeader(defaultHeader.Key, defaultHeader.Value);
-      }
-
-      _request.AddUrlSegment("format", "json"); // set format to json by default
-      _request.AddUrlSegment("orderId", ApiInvoker.ParameterToString(OrderId)); // path (url segment) parameter
+      var path = "/store/order/{orderId}";
+      path = path.Replace("{format}", "json");
+      path = path.Replace("{" + "orderId" + "}", apiClient.ParameterToString(OrderId));
       
+
+      var queryParams = new Dictionary<String, String>();
+      var headerParams = new Dictionary<String, String>();
+      var formParams = new Dictionary<String, String>();
+      var fileParams = new Dictionary<String, String>();
+      String postBody = null;
+
       
       
       
       
 
       // make the HTTP request
-      IRestResponse response = restClient.Execute(_request);
+      IRestResponse response = (IRestResponse) apiClient.CallApi("/store/order/{orderId}", Method.DELETE, queryParams, postBody, headerParams, formParams, fileParams);
+
       if (((int)response.StatusCode) >= 400) {
         throw new ApiException ((int)response.StatusCode, "Error calling DeleteOrder: " + response.Content);
       }
diff --git a/samples/client/petstore/csharp/src/main/csharp/io/swagger/Api/UserApi.cs b/samples/client/petstore/csharp/src/main/csharp/io/swagger/Api/UserApi.cs
index ff8f23a18b2e..c225f45496de 100644
--- a/samples/client/petstore/csharp/src/main/csharp/io/swagger/Api/UserApi.cs
+++ b/samples/client/petstore/csharp/src/main/csharp/io/swagger/Api/UserApi.cs
@@ -8,12 +8,12 @@ namespace IO.Swagger.Api {
   
   public class UserApi {
     string basePath;
-    protected RestClient restClient;
+    public ApiInvoker apiClient {get; set;}
 
     public UserApi(String basePath = "http://petstore.swagger.io/v2")
     {
       this.basePath = basePath;
-      this.restClient = new RestClient(basePath);
+      this.apiClient = new ApiInvoker(basePath);
     }
 
     /// <summary>
@@ -42,26 +42,27 @@ namespace IO.Swagger.Api {
     /// <returns></returns>
     public void CreateUser (User Body) {
 
-      var _request = new RestRequest("/user", Method.POST);
-
       
 
-      // add default header, if any
-      foreach(KeyValuePair<string, string> defaultHeader in ApiInvoker.GetDefaultHeader())
-      {
-        _request.AddHeader(defaultHeader.Key, defaultHeader.Value);
-      }
+      var path = "/user";
+      path = path.Replace("{format}", "json");
+      
+
+      var queryParams = new Dictionary<String, String>();
+      var headerParams = new Dictionary<String, String>();
+      var formParams = new Dictionary<String, String>();
+      var fileParams = new Dictionary<String, String>();
+      String postBody = null;
 
-      _request.AddUrlSegment("format", "json"); // set format to json by default
       
       
       
-      
-      _request.AddParameter("application/json", ApiInvoker.Serialize(Body), ParameterType.RequestBody); // http body (model) parameter
+      postBody = apiClient.Serialize(Body); // http body (model) parameter
       
 
       // make the HTTP request
-      IRestResponse response = restClient.Execute(_request);
+      IRestResponse response = (IRestResponse) apiClient.CallApi("/user", Method.POST, queryParams, postBody, headerParams, formParams, fileParams);
+
       if (((int)response.StatusCode) >= 400) {
         throw new ApiException ((int)response.StatusCode, "Error calling CreateUser: " + response.Content);
       }
@@ -77,26 +78,27 @@ namespace IO.Swagger.Api {
     /// <returns></returns>
     public void CreateUsersWithArrayInput (List<User> Body) {
 
-      var _request = new RestRequest("/user/createWithArray", Method.POST);
-
       
 
-      // add default header, if any
-      foreach(KeyValuePair<string, string> defaultHeader in ApiInvoker.GetDefaultHeader())
-      {
-        _request.AddHeader(defaultHeader.Key, defaultHeader.Value);
-      }
+      var path = "/user/createWithArray";
+      path = path.Replace("{format}", "json");
+      
+
+      var queryParams = new Dictionary<String, String>();
+      var headerParams = new Dictionary<String, String>();
+      var formParams = new Dictionary<String, String>();
+      var fileParams = new Dictionary<String, String>();
+      String postBody = null;
 
-      _request.AddUrlSegment("format", "json"); // set format to json by default
       
       
       
-      
-      _request.AddParameter("application/json", ApiInvoker.Serialize(Body), ParameterType.RequestBody); // http body (model) parameter
+      postBody = apiClient.Serialize(Body); // http body (model) parameter
       
 
       // make the HTTP request
-      IRestResponse response = restClient.Execute(_request);
+      IRestResponse response = (IRestResponse) apiClient.CallApi("/user/createWithArray", Method.POST, queryParams, postBody, headerParams, formParams, fileParams);
+
       if (((int)response.StatusCode) >= 400) {
         throw new ApiException ((int)response.StatusCode, "Error calling CreateUsersWithArrayInput: " + response.Content);
       }
@@ -112,26 +114,27 @@ namespace IO.Swagger.Api {
     /// <returns></returns>
     public void CreateUsersWithListInput (List<User> Body) {
 
-      var _request = new RestRequest("/user/createWithList", Method.POST);
-
       
 
-      // add default header, if any
-      foreach(KeyValuePair<string, string> defaultHeader in ApiInvoker.GetDefaultHeader())
-      {
-        _request.AddHeader(defaultHeader.Key, defaultHeader.Value);
-      }
+      var path = "/user/createWithList";
+      path = path.Replace("{format}", "json");
+      
+
+      var queryParams = new Dictionary<String, String>();
+      var headerParams = new Dictionary<String, String>();
+      var formParams = new Dictionary<String, String>();
+      var fileParams = new Dictionary<String, String>();
+      String postBody = null;
 
-      _request.AddUrlSegment("format", "json"); // set format to json by default
       
       
       
-      
-      _request.AddParameter("application/json", ApiInvoker.Serialize(Body), ParameterType.RequestBody); // http body (model) parameter
+      postBody = apiClient.Serialize(Body); // http body (model) parameter
       
 
       // make the HTTP request
-      IRestResponse response = restClient.Execute(_request);
+      IRestResponse response = (IRestResponse) apiClient.CallApi("/user/createWithList", Method.POST, queryParams, postBody, headerParams, formParams, fileParams);
+
       if (((int)response.StatusCode) >= 400) {
         throw new ApiException ((int)response.StatusCode, "Error calling CreateUsersWithListInput: " + response.Content);
       }
@@ -148,31 +151,32 @@ namespace IO.Swagger.Api {
     /// <returns>string</returns>
     public string LoginUser (string Username, string Password) {
 
-      var _request = new RestRequest("/user/login", Method.GET);
-
       
 
-      // add default header, if any
-      foreach(KeyValuePair<string, string> defaultHeader in ApiInvoker.GetDefaultHeader())
-      {
-        _request.AddHeader(defaultHeader.Key, defaultHeader.Value);
-      }
-
-      _request.AddUrlSegment("format", "json"); // set format to json by default
+      var path = "/user/login";
+      path = path.Replace("{format}", "json");
       
-       if (Username != null) _request.AddParameter("username", ApiInvoker.ParameterToString(Username)); // query parameter
-       if (Password != null) _request.AddParameter("password", ApiInvoker.ParameterToString(Password)); // query parameter
+
+      var queryParams = new Dictionary<String, String>();
+      var headerParams = new Dictionary<String, String>();
+      var formParams = new Dictionary<String, String>();
+      var fileParams = new Dictionary<String, String>();
+      String postBody = null;
+
+       if (Username != null) queryParams.Add("username", apiClient.ParameterToString(Username)); // query parameter
+       if (Password != null) queryParams.Add("password", apiClient.ParameterToString(Password)); // query parameter
       
       
       
       
 
       // make the HTTP request
-      IRestResponse response = restClient.Execute(_request);
+      IRestResponse response = (IRestResponse) apiClient.CallApi("/user/login", Method.GET, queryParams, postBody, headerParams, formParams, fileParams);
+
       if (((int)response.StatusCode) >= 400) {
         throw new ApiException ((int)response.StatusCode, "Error calling LoginUser: " + response.Content);
       }
-      return (string) ApiInvoker.Deserialize(response.Content, typeof(string));
+      return (string) apiClient.Deserialize(response.Content, typeof(string));
     }
     
     
@@ -182,25 +186,26 @@ namespace IO.Swagger.Api {
     /// <returns></returns>
     public void LogoutUser () {
 
-      var _request = new RestRequest("/user/logout", Method.GET);
-
       
 
-      // add default header, if any
-      foreach(KeyValuePair<string, string> defaultHeader in ApiInvoker.GetDefaultHeader())
-      {
-        _request.AddHeader(defaultHeader.Key, defaultHeader.Value);
-      }
-
-      _request.AddUrlSegment("format", "json"); // set format to json by default
+      var path = "/user/logout";
+      path = path.Replace("{format}", "json");
       
+
+      var queryParams = new Dictionary<String, String>();
+      var headerParams = new Dictionary<String, String>();
+      var formParams = new Dictionary<String, String>();
+      var fileParams = new Dictionary<String, String>();
+      String postBody = null;
+
       
       
       
       
 
       // make the HTTP request
-      IRestResponse response = restClient.Execute(_request);
+      IRestResponse response = (IRestResponse) apiClient.CallApi("/user/logout", Method.GET, queryParams, postBody, headerParams, formParams, fileParams);
+
       if (((int)response.StatusCode) >= 400) {
         throw new ApiException ((int)response.StatusCode, "Error calling LogoutUser: " + response.Content);
       }
@@ -216,33 +221,34 @@ namespace IO.Swagger.Api {
     /// <returns>User</returns>
     public User GetUserByName (string Username) {
 
-      var _request = new RestRequest("/user/{username}", Method.GET);
-
       
       // verify the required parameter 'Username' is set
       if (Username == null) throw new ApiException(400, "Missing required parameter 'Username' when calling GetUserByName");
       
 
-      // add default header, if any
-      foreach(KeyValuePair<string, string> defaultHeader in ApiInvoker.GetDefaultHeader())
-      {
-        _request.AddHeader(defaultHeader.Key, defaultHeader.Value);
-      }
-
-      _request.AddUrlSegment("format", "json"); // set format to json by default
-      _request.AddUrlSegment("username", ApiInvoker.ParameterToString(Username)); // path (url segment) parameter
+      var path = "/user/{username}";
+      path = path.Replace("{format}", "json");
+      path = path.Replace("{" + "username" + "}", apiClient.ParameterToString(Username));
       
+
+      var queryParams = new Dictionary<String, String>();
+      var headerParams = new Dictionary<String, String>();
+      var formParams = new Dictionary<String, String>();
+      var fileParams = new Dictionary<String, String>();
+      String postBody = null;
+
       
       
       
       
 
       // make the HTTP request
-      IRestResponse response = restClient.Execute(_request);
+      IRestResponse response = (IRestResponse) apiClient.CallApi("/user/{username}", Method.GET, queryParams, postBody, headerParams, formParams, fileParams);
+
       if (((int)response.StatusCode) >= 400) {
         throw new ApiException ((int)response.StatusCode, "Error calling GetUserByName: " + response.Content);
       }
-      return (User) ApiInvoker.Deserialize(response.Content, typeof(User));
+      return (User) apiClient.Deserialize(response.Content, typeof(User));
     }
     
     
@@ -254,30 +260,31 @@ namespace IO.Swagger.Api {
     /// <returns></returns>
     public void UpdateUser (string Username, User Body) {
 
-      var _request = new RestRequest("/user/{username}", Method.PUT);
-
       
       // verify the required parameter 'Username' is set
       if (Username == null) throw new ApiException(400, "Missing required parameter 'Username' when calling UpdateUser");
       
 
-      // add default header, if any
-      foreach(KeyValuePair<string, string> defaultHeader in ApiInvoker.GetDefaultHeader())
-      {
-        _request.AddHeader(defaultHeader.Key, defaultHeader.Value);
-      }
+      var path = "/user/{username}";
+      path = path.Replace("{format}", "json");
+      path = path.Replace("{" + "username" + "}", apiClient.ParameterToString(Username));
+      
+
+      var queryParams = new Dictionary<String, String>();
+      var headerParams = new Dictionary<String, String>();
+      var formParams = new Dictionary<String, String>();
+      var fileParams = new Dictionary<String, String>();
+      String postBody = null;
 
-      _request.AddUrlSegment("format", "json"); // set format to json by default
-      _request.AddUrlSegment("username", ApiInvoker.ParameterToString(Username)); // path (url segment) parameter
       
       
       
-      
-      _request.AddParameter("application/json", ApiInvoker.Serialize(Body), ParameterType.RequestBody); // http body (model) parameter
+      postBody = apiClient.Serialize(Body); // http body (model) parameter
       
 
       // make the HTTP request
-      IRestResponse response = restClient.Execute(_request);
+      IRestResponse response = (IRestResponse) apiClient.CallApi("/user/{username}", Method.PUT, queryParams, postBody, headerParams, formParams, fileParams);
+
       if (((int)response.StatusCode) >= 400) {
         throw new ApiException ((int)response.StatusCode, "Error calling UpdateUser: " + response.Content);
       }
@@ -293,29 +300,30 @@ namespace IO.Swagger.Api {
     /// <returns></returns>
     public void DeleteUser (string Username) {
 
-      var _request = new RestRequest("/user/{username}", Method.DELETE);
-
       
       // verify the required parameter 'Username' is set
       if (Username == null) throw new ApiException(400, "Missing required parameter 'Username' when calling DeleteUser");
       
 
-      // add default header, if any
-      foreach(KeyValuePair<string, string> defaultHeader in ApiInvoker.GetDefaultHeader())
-      {
-        _request.AddHeader(defaultHeader.Key, defaultHeader.Value);
-      }
-
-      _request.AddUrlSegment("format", "json"); // set format to json by default
-      _request.AddUrlSegment("username", ApiInvoker.ParameterToString(Username)); // path (url segment) parameter
+      var path = "/user/{username}";
+      path = path.Replace("{format}", "json");
+      path = path.Replace("{" + "username" + "}", apiClient.ParameterToString(Username));
       
+
+      var queryParams = new Dictionary<String, String>();
+      var headerParams = new Dictionary<String, String>();
+      var formParams = new Dictionary<String, String>();
+      var fileParams = new Dictionary<String, String>();
+      String postBody = null;
+
       
       
       
       
 
       // make the HTTP request
-      IRestResponse response = restClient.Execute(_request);
+      IRestResponse response = (IRestResponse) apiClient.CallApi("/user/{username}", Method.DELETE, queryParams, postBody, headerParams, formParams, fileParams);
+
       if (((int)response.StatusCode) >= 400) {
         throw new ApiException ((int)response.StatusCode, "Error calling DeleteUser: " + response.Content);
       }
diff --git a/samples/client/petstore/csharp/src/main/csharp/io/swagger/client/ApiInvoker.cs b/samples/client/petstore/csharp/src/main/csharp/io/swagger/client/ApiInvoker.cs
index 8bb364728353..ce5cf0263eb6 100644
--- a/samples/client/petstore/csharp/src/main/csharp/io/swagger/client/ApiInvoker.cs
+++ b/samples/client/petstore/csharp/src/main/csharp/io/swagger/client/ApiInvoker.cs
@@ -5,10 +5,54 @@ using System.Linq;
 using System.Net;
 using System.Text;
 using Newtonsoft.Json;
+using RestSharp;
 
 namespace IO.Swagger.Client {
   public class ApiInvoker {
-    private static Dictionary<String, String> defaultHeaderMap = new Dictionary<String, String>();
+    public ApiInvoker() {
+      this.basePath = "http://petstore.swagger.io/v2";
+    }
+
+    public ApiInvoker(String basePath) {
+      this.basePath = basePath;
+    }
+
+    public string basePath { get; set; }
+    public RestClient restClient { get; set; }
+    private Dictionary<String, String> defaultHeaderMap = new Dictionary<String, String>();
+
+    public Object CallApi(String Path, RestSharp.Method Method, Dictionary<String, String> QueryParams, String PostBody, 
+      Dictionary<String, String> HeaderParams, Dictionary<String, String> FormParams, Dictionary<String, String> FileParams) {
+
+      var request = new RestRequest(Path, Method);
+
+      // add default header, if any
+      foreach(KeyValuePair<string, string> defaultHeader in this.defaultHeaderMap)
+        request.AddHeader(defaultHeader.Key, defaultHeader.Value);
+
+      // add header parameter, if any
+      foreach(KeyValuePair<string, string> param in HeaderParams)
+        request.AddHeader(param.Key, param.Value);
+     
+      // add query parameter, if any
+      foreach(KeyValuePair<string, string> param in QueryParams)
+        request.AddUrlSegment(param.Key, param.Value);
+
+      // add form parameter, if any
+      foreach(KeyValuePair<string, string> param in FormParams)
+        request.AddParameter(param.Key, param.Value);
+
+      // add file parameter, if any
+      foreach(KeyValuePair<string, string> param in FormParams)
+        request.AddFile(param.Key, param.Value);
+
+      if (PostBody == null) {
+        request.AddParameter("application/json", PostBody, ParameterType.RequestBody); // http body (model) parameter
+      }
+
+      return (Object)restClient.Execute(request);
+
+    }
 
     /// <summary>
     /// Add default header
@@ -16,7 +60,7 @@ namespace IO.Swagger.Client {
     /// <param name="key">  Header field name
     /// <param name="value"> Header field value
     /// <returns></returns>
-    public static void AddDefaultHeader(string key, string value) {
+    public void AddDefaultHeader(string key, string value) {
        defaultHeaderMap.Add(key, value);
     }
 
@@ -24,7 +68,7 @@ namespace IO.Swagger.Client {
     /// Get default header
     /// </summary>
     /// <returns>Dictionary of default header</returns>
-    public static Dictionary<String, String> GetDefaultHeader() {
+    public Dictionary<String, String> GetDefaultHeader() {
        return defaultHeaderMap;
     }
 
@@ -33,7 +77,7 @@ namespace IO.Swagger.Client {
     /// </summary>
     /// <param name="str"> String to be escaped
     /// <returns>Escaped string</returns>
-    public static string EscapeString(string str) {
+    public string EscapeString(string str) {
       return str;
     }
 
@@ -42,7 +86,7 @@ namespace IO.Swagger.Client {
     /// </summary>
     /// <param name="obj"> The parameter (header, path, query, form)
     /// <returns>Formatted string</returns>
-    public static string ParameterToString(object obj)
+    public string ParameterToString(object obj)
     {
       return (obj is DateTime) ? ((DateTime)obj).ToString ("u") : Convert.ToString (obj);
     }
@@ -53,7 +97,7 @@ namespace IO.Swagger.Client {
     /// <param name="json"> JSON string
     /// <param name="type"> Object type
     /// <returns>Object representation of the JSON string</returns>
-    public static object Deserialize(string content, Type type) {
+    public object Deserialize(string content, Type type) {
       if (type.GetType() == typeof(Object))
         return (Object)content;
 
@@ -71,7 +115,7 @@ namespace IO.Swagger.Client {
     /// </summary>
     /// <param name="obj"> Object 
     /// <returns>JSON string</returns>
-    public static string Serialize(object obj) {
+    public string Serialize(object obj) {
       try
       {
           return obj != null ? JsonConvert.SerializeObject(obj) : null;