diff --git a/modules/swagger-codegen/src/main/java/com/wordnik/swagger/codegen/languages/CSharpClientCodegen.java b/modules/swagger-codegen/src/main/java/com/wordnik/swagger/codegen/languages/CSharpClientCodegen.java
index 969b143c5a0..13a16747483 100644
--- a/modules/swagger-codegen/src/main/java/com/wordnik/swagger/codegen/languages/CSharpClientCodegen.java
+++ b/modules/swagger-codegen/src/main/java/com/wordnik/swagger/codegen/languages/CSharpClientCodegen.java
@@ -80,7 +80,7 @@ public class CSharpClientCodegen extends DefaultCodegen implements CodegenConfig
     typeMapping.put("double", "double?");
     typeMapping.put("number", "double?");
     typeMapping.put("Date", "DateTime");
-    typeMapping.put("file", "byte[]");
+    typeMapping.put("file", "string"); // path to file
     typeMapping.put("array", "List");
     typeMapping.put("map", "Dictionary");
 
diff --git a/modules/swagger-codegen/src/main/resources/csharp/api.mustache b/modules/swagger-codegen/src/main/resources/csharp/api.mustache
index d2fd1835f3b..ea0e9ab0786 100644
--- a/modules/swagger-codegen/src/main/resources/csharp/api.mustache
+++ b/modules/swagger-codegen/src/main/resources/csharp/api.mustache
@@ -10,36 +10,38 @@ namespace {{package}} {
   {{#operations}}
   public class {{classname}} {
     string basePath;
-    private readonly ApiInvoker apiInvoker = ApiInvoker.GetInstance();
-    protected RestClient _client;
+    protected RestClient restClient;
 
     public {{classname}}(String basePath = "{{basePath}}")
     {
       this.basePath = basePath;
-      _client = new RestClient(basePath);
+      this.restClient = new RestClient(basePath);
     }
 
-    public ApiInvoker getInvoker() {
-      return apiInvoker;
-    }
-
-    // Sets the endpoint base url for the services being accessed
-    public void setBasePath(string basePath) {
+    /// <summary>
+    /// Sets the endpoint base url for the services being accessed
+    /// </summary>
+    /// <param name="basePath"> Base URL
+    /// <returns></returns>
+    public void SetBasePath(string basePath) {
       this.basePath = basePath;
     }
 
-    // Gets the endpoint base url for the services being accessed
-    public String getBasePath() {
-      return basePath;
+    /// <summary>
+    /// Gets the endpoint base url for the services being accessed
+    /// <returns>Base URL</returns>
+    /// </summary>
+    public String GetBasePath() {
+      return this.basePath;
     }
 
     {{#operation}}
-
+    
     /// <summary>
     /// {{summary}} {{notes}}
     /// </summary>
     {{#allParams}}/// <param name="{{paramName}}">{{description}}</param>
-    {{#hasMore}} {{/hasMore}}{{/allParams}}
+    {{/allParams}}
     /// <returns></returns>
     public {{#returnType}}{{{returnType}}} {{/returnType}}{{^returnType}}void {{/returnType}} {{nickname}} ({{#allParams}}{{{dataType}}} {{paramName}}{{#hasMore}}, {{/hasMore}}{{/allParams}}) {
 
@@ -52,20 +54,23 @@ namespace {{package}} {
 
       // path (url segment) parameters
       _request.AddUrlSegment("format", "json"); // set format to json by default
-      {{#pathParams}}_request.AddUrlSegment("{{baseName}}", apiInvoker.ParameterToString({{{paramName}}}));{{/pathParams}}
+      {{#pathParams}}_request.AddUrlSegment("{{baseName}}", ApiInvoker.ParameterToString({{{paramName}}}));{{/pathParams}}
       // query parameters, if any
       {{#queryParams}} if ({{paramName}} != null) _request.AddParameter("{{baseName}}", {{paramName}});{{/queryParams}}
       // header parameters, if any
       {{#headerParams}} if ({{paramName}} != null) _request.AddHeader("{{baseName}}", {{paramName}});{{/headerParams}}
       // form parameters, if any
-      {{#formParams}}if ({{paramName}} != null) {{#isFile}}_request.AddParameter("{{baseName}}", {{paramName}});{{/isFile}}{{^isFile}}_request.AddFile("{{baseName}}", {{paramName}});{{/isFile}}
+      {{#formParams}}if ({{paramName}} != null) {{#isFile}}_request.AddFile("{{baseName}}", {{paramName}});{{/isFile}}{{^isFile}}_request.AddParameter("{{baseName}}", {{paramName}});{{/isFile}}
       {{/formParams}}
+      {{#bodyParam}}
+      _request.AddParameter("application/json", ApiInvoker.Serialize({{paramName}}), ParameterType.RequestBody);
+      {{/bodyParam}}
 
       try {
-        {{#returnType}}IRestResponse response = _client.Execute(_request);
-        return ({{{returnType}}}) ApiInvoker.deserialize(response.Content, typeof({{{returnType}}}));
+        {{#returnType}}IRestResponse response = restClient.Execute(_request);
+        return ({{{returnType}}}) ApiInvoker.Deserialize(response.Content, typeof({{{returnType}}}));
         //return ((object)response) as {{{returnType}}};{{/returnType}}
-        {{^returnType}}_client.Execute(_request);
+        {{^returnType}}restClient.Execute(_request);
         return;{{/returnType}}
       } catch (Exception ex) {
         if(ex != null) {
diff --git a/modules/swagger-codegen/src/main/resources/csharp/apiInvoker.mustache b/modules/swagger-codegen/src/main/resources/csharp/apiInvoker.mustache
index 4e7f1b6997b..9beebc19231 100644
--- a/modules/swagger-codegen/src/main/resources/csharp/apiInvoker.mustache
+++ b/modules/swagger-codegen/src/main/resources/csharp/apiInvoker.mustache
@@ -1,235 +1,81 @@
-  using System;
-  using System.Collections.Generic;
-  using System.IO;
-  using System.Linq;
-  using System.Net;
-  using System.Text;
-  using Newtonsoft.Json;
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Net;
+using System.Text;
+using Newtonsoft.Json;
 
-  namespace {{invokerPackage}} {
-    public class ApiInvoker {
-      private static readonly ApiInvoker _instance = new ApiInvoker();
-      private Dictionary<String, String> defaultHeaderMap = new Dictionary<String, String>();
+namespace {{invokerPackage}} {
+  public class ApiInvoker {
+    private static Dictionary<String, String> defaultHeaderMap = new Dictionary<String, String>();
 
-      public static ApiInvoker GetInstance() {
-        return _instance;
-      }
+    /// <summary>
+    /// Add default header
+    /// </summary>
+    /// <param name="key">  Header field name
+    /// <param name="value"> Header field value
+    /// <returns></returns>
+    public static void AddDefaultHeader(string key, string value) {
+       defaultHeaderMap.Add(key, value);
+    }
 
-      /// <summary>
-      /// Add default header
-      /// </summary>
-      /// <param name="key">  Header field name
-      /// <param name="value"> Header field value
-      /// <returns></returns>
-      public void addDefaultHeader(string key, string value) {
-         defaultHeaderMap.Add(key, value);
-      }
+    /// <summary>
+    /// Get default header
+    /// </summary>
+    /// <returns>Dictionary of default header</returns>
+    public static Dictionary<String, String> GetDefaultHeader() {
+       return defaultHeaderMap;
+    }
 
-      /// <summary>
-      /// escape string (url-encoded)
-      /// </summary>
-      /// <param name="str"> String to be escaped
-      /// <returns>Escaped string</returns>
-      public string escapeString(string str) {
-        return str;
-      }
+    /// <summary>
+    /// escape string (url-encoded)
+    /// </summary>
+    /// <param name="str"> String to be escaped
+    /// <returns>Escaped string</returns>
+    public static string EscapeString(string str) {
+      return str;
+    }
 
-      /// <summary>
-      /// if parameter is DateTime, output in ISO8601 format, otherwise just return the string
-      /// </summary>
-      /// <param name="obj"> The parameter (header, path, query, form)
-      /// <returns>Formatted string</returns>
-      public string ParameterToString(object obj)
+    /// <summary>
+    /// if parameter is DateTime, output in ISO8601 format, otherwise just return the string
+    /// </summary>
+    /// <param name="obj"> The parameter (header, path, query, form)
+    /// <returns>Formatted string</returns>
+    public static string ParameterToString(object obj)
+    {
+      return (obj is DateTime) ? ((DateTime)obj).ToString ("u") : Convert.ToString (obj);
+    }
+
+    /// <summary>
+    /// Deserialize the JSON string into a proper object
+    /// </summary>
+    /// <param name="json"> JSON string
+    /// <param name="type"> Object type
+    /// <returns>Object representation of the JSON string</returns>
+    public static object Deserialize(string json, Type type) {
+      try
       {
-        return (obj is DateTime) ? ((DateTime)obj).ToString ("u") : Convert.ToString (obj);
+          return JsonConvert.DeserializeObject(json, type);
       }
-
-      /// <summary>
-      /// Deserialize the JSON string into a proper object
-      /// </summary>
-      /// <param name="json"> JSON string
-      /// <param name="type"> Object type
-      /// <returns>Object representation of the JSON string</returns>
-      public static object deserialize(string json, Type type) {
-        try
-        {
-            return JsonConvert.DeserializeObject(json, type);
-        }
-        catch (IOException e) {
-          throw new ApiException(500, e.Message);
-        }
-
+      catch (IOException e) {
+        throw new ApiException(500, e.Message);
       }
+    }
 
-      public static string serialize(object obj) {
-        try
-        {
-            return obj != null ? JsonConvert.SerializeObject(obj) : null;
-        }
-        catch (Exception e) {
-          throw new ApiException(500, e.Message);
-        }
-      }
-
-      public string invokeAPI(string host, string path, string method, Dictionary<String, String> queryParams, object body, Dictionary<String, String> headerParams, Dictionary<String, object> formParams)
+    /// <summary>
+    /// Serialize an object into JSON string
+    /// </summary>
+    /// <param name="obj"> Object 
+    /// <returns>JSON string</returns>
+    public static string Serialize(object obj) {
+      try
       {
-          return invokeAPIInternal(host, path, method, false, queryParams, body, headerParams, formParams) as string;
+          return obj != null ? JsonConvert.SerializeObject(obj) : null;
       }
-
-      public byte[] invokeBinaryAPI(string host, string path, string method, Dictionary<String, String> queryParams, object body, Dictionary<String, String> headerParams, Dictionary<String, object> formParams)
-      {
-          return invokeAPIInternal(host, path, method, true, queryParams, body, headerParams, formParams) as byte[];
-      }
-
-      private object invokeAPIInternal(string host, string path, string method, bool binaryResponse, Dictionary<String, String> queryParams, object body, Dictionary<String, String> headerParams, Dictionary<String, object> formParams) {
-        var b = new StringBuilder();
-
-        foreach (var queryParamItem in queryParams)
-        {
-            var value = queryParamItem.Value;
-            if (value == null) continue;
-            b.Append(b.ToString().Length == 0 ? "?" : "&");
-            b.Append(escapeString(queryParamItem.Key)).Append("=").Append(escapeString(value));
-        }
-
-        var querystring = b.ToString();
-
-          host = host.EndsWith("/") ? host.Substring(0, host.Length - 1) : host;
-
-          var client = WebRequest.Create(host + path + querystring);
-          client.Method = method;
-
-          byte[] formData = null;
-          if (formParams.Count > 0)
-          {
-              string formDataBoundary = String.Format("----------{0:N}", Guid.NewGuid());
-              client.ContentType = "multipart/form-data; boundary=" + formDataBoundary;
-              formData = GetMultipartFormData(formParams, formDataBoundary);
-              client.ContentLength = formData.Length;
-          }
-          else
-          {
-              client.ContentType = "application/json";
-          }
-
-          foreach (var headerParamsItem in headerParams)
-          {
-              client.Headers.Add(headerParamsItem.Key, headerParamsItem.Value);
-          }
-          foreach (var defaultHeaderMapItem in defaultHeaderMap.Where(defaultHeaderMapItem => !headerParams.ContainsKey(defaultHeaderMapItem.Key)))
-          {
-              client.Headers.Add(defaultHeaderMapItem.Key, defaultHeaderMapItem.Value);
-          }
-
-          switch (method)
-          {
-              case "GET":
-                  break;
-              case "POST":
-              case "PATCH":
-              case "PUT":
-              case "DELETE":
-                  using (Stream requestStream = client.GetRequestStream())
-                  {
-                      if (formData != null)
-                      {
-                          requestStream.Write(formData, 0, formData.Length);
-                      }
-
-                      var swRequestWriter = new StreamWriter(requestStream);
-                      swRequestWriter.Write(serialize(body));
-                      swRequestWriter.Close();
-                  }
-                  break;
-              default:
-                  throw new ApiException(500, "unknown method type " + method);
-          }
-
-          try
-          {
-              var webResponse = (HttpWebResponse)client.GetResponse();
-              if (webResponse.StatusCode != HttpStatusCode.OK)
-              {
-                  webResponse.Close();
-                  throw new ApiException((int)webResponse.StatusCode, webResponse.StatusDescription);
-              }
-
-              if (binaryResponse)
-              {
-                  using (var memoryStream = new MemoryStream())
-                  {
-                      webResponse.GetResponseStream().CopyTo(memoryStream);
-                      return memoryStream.ToArray();
-                  }
-              }
-              else
-              {
-                  using (var responseReader = new StreamReader(webResponse.GetResponseStream()))
-                  {
-                      var responseData = responseReader.ReadToEnd();
-                      return responseData;
-                  }
-              }
-          }
-          catch(WebException ex)
-          {
-              var response = ex.Response as HttpWebResponse;
-              int statusCode = 0;
-              if (response != null)
-              {
-                  statusCode = (int)response.StatusCode;
-                  response.Close();
-              }
-              throw new ApiException(statusCode, ex.Message);
-          }
-      }
-
-      private static byte[] GetMultipartFormData(Dictionary<string, object> postParameters, string boundary)
-      {
-          Stream formDataStream = new System.IO.MemoryStream();
-          bool needsCLRF = false;
-
-          foreach (var param in postParameters)
-          {
-              // Thanks to feedback from commenters, add a CRLF to allow multiple parameters to be added.
-              // Skip it on the first parameter, add it to subsequent parameters.
-              if (needsCLRF)
-                  formDataStream.Write(Encoding.UTF8.GetBytes("\r\n"), 0, Encoding.UTF8.GetByteCount("\r\n"));
-
-              needsCLRF = true;
-
-              if (param.Value is byte[])
-              {
-                  string postData = string.Format("--{0}\r\nContent-Disposition: form-data; name=\"{1}\"; filename=\"{1}\"\r\nContent-Type: {2}\r\n\r\n",
-                      boundary,
-                      param.Key,
-                      "application/octet-stream");
-                  formDataStream.Write(Encoding.UTF8.GetBytes(postData), 0, Encoding.UTF8.GetByteCount(postData));
-
-                  // Write the file data directly to the Stream, rather than serializing it to a string.
-                  formDataStream.Write((param.Value as byte[]), 0, (param.Value as byte[]).Length);
-              }
-              else
-              {
-                  string postData = string.Format("--{0}\r\nContent-Disposition: form-data; name=\"{1}\"\r\n\r\n{2}",
-                      boundary,
-                      param.Key,
-                      param.Value);
-                  formDataStream.Write(Encoding.UTF8.GetBytes(postData), 0, Encoding.UTF8.GetByteCount(postData));
-              }
-          }
-
-          // Add the end of the request.  Start with a newline
-          string footer = "\r\n--" + boundary + "--\r\n";
-          formDataStream.Write(Encoding.UTF8.GetBytes(footer), 0, Encoding.UTF8.GetByteCount(footer));
-
-          // Dump the Stream into a byte[]
-          formDataStream.Position = 0;
-          byte[] formData = new byte[formDataStream.Length];
-          formDataStream.Read(formData, 0, formData.Length);
-          formDataStream.Close();
-
-          return formData;
+      catch (Exception e) {
+        throw new ApiException(500, e.Message);
       }
     }
   }
+}
diff --git a/modules/swagger-codegen/src/main/resources/csharp/model.mustache b/modules/swagger-codegen/src/main/resources/csharp/model.mustache
index d9ef4ffbedd..a8a3aa3a7a2 100644
--- a/modules/swagger-codegen/src/main/resources/csharp/model.mustache
+++ b/modules/swagger-codegen/src/main/resources/csharp/model.mustache
@@ -2,19 +2,19 @@ using System;
 using System.Text;
 using System.Collections;
 using System.Collections.Generic;
+using System.Runtime.Serialization;
 
 {{#models}}
 {{#model}}
 namespace {{package}} {
+  [DataContract]
   public class {{classname}} {
     {{#vars}}
-
-    {{#description}}/* {{{description}}} */
-    {{/description}}
+    {{#description}}/* {{{description}}} */{{/description}}
+    [DataMember(Name="{{baseName}}", EmitDefaultValue=false)]
     public {{{datatype}}} {{name}} { get; set; }
 
     {{/vars}}
-
     public override string ToString()  {
       var sb = new StringBuilder();
       sb.Append("class {{classname}} {\n");
@@ -27,4 +27,4 @@ namespace {{package}} {
   }
   {{/model}}
   {{/models}}
-}
\ No newline at end of file
+}
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 ec781454cbb..e039513c581 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
@@ -8,31 +8,33 @@ namespace io.swagger.Api {
   
   public class PetApi {
     string basePath;
-    private readonly ApiInvoker apiInvoker = ApiInvoker.GetInstance();
-    protected RestClient _client;
+    protected RestClient restClient;
 
     public PetApi(String basePath = "http://petstore.swagger.io/v2")
     {
       this.basePath = basePath;
-      _client = new RestClient(basePath);
+      this.restClient = new RestClient(basePath);
     }
 
-    public ApiInvoker getInvoker() {
-      return apiInvoker;
-    }
-
-    // Sets the endpoint base url for the services being accessed
-    public void setBasePath(string basePath) {
+    /// <summary>
+    /// Sets the endpoint base url for the services being accessed
+    /// </summary>
+    /// <param name="basePath"> Base URL
+    /// <returns></returns>
+    public void SetBasePath(string basePath) {
       this.basePath = basePath;
     }
 
-    // Gets the endpoint base url for the services being accessed
-    public String getBasePath() {
-      return basePath;
+    /// <summary>
+    /// Gets the endpoint base url for the services being accessed
+    /// <returns>Base URL</returns>
+    /// </summary>
+    public String GetBasePath() {
+      return this.basePath;
     }
 
     
-
+    
     /// <summary>
     /// Update an existing pet 
     /// </summary>
@@ -56,10 +58,13 @@ namespace io.swagger.Api {
       
       // form parameters, if any
       
+      
+      _request.AddParameter("application/json", ApiInvoker.Serialize(Body), ParameterType.RequestBody);
+      
 
       try {
         
-        _client.Execute(_request);
+        restClient.Execute(_request);
         return;
       } catch (Exception ex) {
         if(ex != null) {
@@ -71,7 +76,7 @@ namespace io.swagger.Api {
       }
     }
     
-
+    
     /// <summary>
     /// Add a new pet to the store 
     /// </summary>
@@ -95,10 +100,13 @@ namespace io.swagger.Api {
       
       // form parameters, if any
       
+      
+      _request.AddParameter("application/json", ApiInvoker.Serialize(Body), ParameterType.RequestBody);
+      
 
       try {
         
-        _client.Execute(_request);
+        restClient.Execute(_request);
         return;
       } catch (Exception ex) {
         if(ex != null) {
@@ -110,7 +118,7 @@ namespace io.swagger.Api {
       }
     }
     
-
+    
     /// <summary>
     /// Finds Pets by status Multiple status values can be provided with comma seperated strings
     /// </summary>
@@ -134,10 +142,11 @@ namespace io.swagger.Api {
       
       // form parameters, if any
       
+      
 
       try {
-        IRestResponse response = _client.Execute(_request);
-        return (List<Pet>) ApiInvoker.deserialize(response.Content, typeof(List<Pet>));
+        IRestResponse response = restClient.Execute(_request);
+        return (List<Pet>) ApiInvoker.Deserialize(response.Content, typeof(List<Pet>));
         //return ((object)response) as List<Pet>;
         
       } catch (Exception ex) {
@@ -150,7 +159,7 @@ namespace io.swagger.Api {
       }
     }
     
-
+    
     /// <summary>
     /// Finds Pets by tags Muliple tags can be provided with comma seperated strings. Use tag1, tag2, tag3 for testing.
     /// </summary>
@@ -174,10 +183,11 @@ namespace io.swagger.Api {
       
       // form parameters, if any
       
+      
 
       try {
-        IRestResponse response = _client.Execute(_request);
-        return (List<Pet>) ApiInvoker.deserialize(response.Content, typeof(List<Pet>));
+        IRestResponse response = restClient.Execute(_request);
+        return (List<Pet>) ApiInvoker.Deserialize(response.Content, typeof(List<Pet>));
         //return ((object)response) as List<Pet>;
         
       } catch (Exception ex) {
@@ -190,7 +200,7 @@ namespace io.swagger.Api {
       }
     }
     
-
+    
     /// <summary>
     /// Find pet by ID Returns a pet when ID &lt; 10.  ID &gt; 10 or nonintegers will simulate API error conditions
     /// </summary>
@@ -207,17 +217,18 @@ namespace io.swagger.Api {
 
       // path (url segment) parameters
       _request.AddUrlSegment("format", "json"); // set format to json by default
-      _request.AddUrlSegment("petId", apiInvoker.ParameterToString(PetId));
+      _request.AddUrlSegment("petId", ApiInvoker.ParameterToString(PetId));
       // query parameters, if any
       
       // header parameters, if any
       
       // form parameters, if any
       
+      
 
       try {
-        IRestResponse response = _client.Execute(_request);
-        return (Pet) ApiInvoker.deserialize(response.Content, typeof(Pet));
+        IRestResponse response = restClient.Execute(_request);
+        return (Pet) ApiInvoker.Deserialize(response.Content, typeof(Pet));
         //return ((object)response) as Pet;
         
       } catch (Exception ex) {
@@ -230,13 +241,13 @@ namespace io.swagger.Api {
       }
     }
     
-
+    
     /// <summary>
     /// Updates a pet in the store with form data 
     /// </summary>
     /// <param name="PetId">ID of pet that needs to be updated</param>
-     /// <param name="Name">Updated name of the pet</param>
-     /// <param name="Status">Updated status of the pet</param>
+    /// <param name="Name">Updated name of the pet</param>
+    /// <param name="Status">Updated status of the pet</param>
     
     /// <returns></returns>
     public void  UpdatePetWithForm (string PetId, string Name, string Status) {
@@ -249,19 +260,20 @@ namespace io.swagger.Api {
 
       // path (url segment) parameters
       _request.AddUrlSegment("format", "json"); // set format to json by default
-      _request.AddUrlSegment("petId", apiInvoker.ParameterToString(PetId));
+      _request.AddUrlSegment("petId", ApiInvoker.ParameterToString(PetId));
       // query parameters, if any
       
       // header parameters, if any
       
       // form parameters, if any
-      if (Name != null) _request.AddFile("name", Name);
-      if (Status != null) _request.AddFile("status", Status);
+      if (Name != null) _request.AddParameter("name", Name);
+      if (Status != null) _request.AddParameter("status", Status);
+      
       
 
       try {
         
-        _client.Execute(_request);
+        restClient.Execute(_request);
         return;
       } catch (Exception ex) {
         if(ex != null) {
@@ -273,12 +285,12 @@ namespace io.swagger.Api {
       }
     }
     
-
+    
     /// <summary>
     /// Deletes a pet 
     /// </summary>
     /// <param name="ApiKey"></param>
-     /// <param name="PetId">Pet id to delete</param>
+    /// <param name="PetId">Pet id to delete</param>
     
     /// <returns></returns>
     public void  DeletePet (string ApiKey, long? PetId) {
@@ -291,17 +303,18 @@ namespace io.swagger.Api {
 
       // path (url segment) parameters
       _request.AddUrlSegment("format", "json"); // set format to json by default
-      _request.AddUrlSegment("petId", apiInvoker.ParameterToString(PetId));
+      _request.AddUrlSegment("petId", ApiInvoker.ParameterToString(PetId));
       // query parameters, if any
       
       // header parameters, if any
        if (ApiKey != null) _request.AddHeader("api_key", ApiKey);
       // form parameters, if any
       
+      
 
       try {
         
-        _client.Execute(_request);
+        restClient.Execute(_request);
         return;
       } catch (Exception ex) {
         if(ex != null) {
@@ -313,13 +326,13 @@ namespace io.swagger.Api {
       }
     }
     
-
+    
     /// <summary>
     /// uploads an image 
     /// </summary>
     /// <param name="PetId">ID of pet to update</param>
-     /// <param name="AdditionalMetadata">Additional data to pass to server</param>
-     /// <param name="File">file to upload</param>
+    /// <param name="AdditionalMetadata">Additional data to pass to server</param>
+    /// <param name="File">file to upload</param>
     
     /// <returns></returns>
     public void  UploadFile (long? PetId, string AdditionalMetadata, byte[] File) {
@@ -332,19 +345,20 @@ namespace io.swagger.Api {
 
       // path (url segment) parameters
       _request.AddUrlSegment("format", "json"); // set format to json by default
-      _request.AddUrlSegment("petId", apiInvoker.ParameterToString(PetId));
+      _request.AddUrlSegment("petId", ApiInvoker.ParameterToString(PetId));
       // query parameters, if any
       
       // header parameters, if any
       
       // form parameters, if any
-      if (AdditionalMetadata != null) _request.AddFile("additionalMetadata", AdditionalMetadata);
-      if (File != null) _request.AddParameter("file", File);
+      if (AdditionalMetadata != null) _request.AddParameter("additionalMetadata", AdditionalMetadata);
+      if (File != null) _request.AddFile("file", File);
+      
       
 
       try {
         
-        _client.Execute(_request);
+        restClient.Execute(_request);
         return;
       } catch (Exception ex) {
         if(ex != null) {
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 e921827d94b..6d0b148ea15 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
@@ -8,31 +8,33 @@ namespace io.swagger.Api {
   
   public class StoreApi {
     string basePath;
-    private readonly ApiInvoker apiInvoker = ApiInvoker.GetInstance();
-    protected RestClient _client;
+    protected RestClient restClient;
 
     public StoreApi(String basePath = "http://petstore.swagger.io/v2")
     {
       this.basePath = basePath;
-      _client = new RestClient(basePath);
+      this.restClient = new RestClient(basePath);
     }
 
-    public ApiInvoker getInvoker() {
-      return apiInvoker;
-    }
-
-    // Sets the endpoint base url for the services being accessed
-    public void setBasePath(string basePath) {
+    /// <summary>
+    /// Sets the endpoint base url for the services being accessed
+    /// </summary>
+    /// <param name="basePath"> Base URL
+    /// <returns></returns>
+    public void SetBasePath(string basePath) {
       this.basePath = basePath;
     }
 
-    // Gets the endpoint base url for the services being accessed
-    public String getBasePath() {
-      return basePath;
+    /// <summary>
+    /// Gets the endpoint base url for the services being accessed
+    /// <returns>Base URL</returns>
+    /// </summary>
+    public String GetBasePath() {
+      return this.basePath;
     }
 
     
-
+    
     /// <summary>
     /// Returns pet inventories by status Returns a map of status codes to quantities
     /// </summary>
@@ -55,10 +57,11 @@ namespace io.swagger.Api {
       
       // form parameters, if any
       
+      
 
       try {
-        IRestResponse response = _client.Execute(_request);
-        return (Dictionary<String, int?>) ApiInvoker.deserialize(response.Content, typeof(Dictionary<String, int?>));
+        IRestResponse response = restClient.Execute(_request);
+        return (Dictionary<String, int?>) ApiInvoker.Deserialize(response.Content, typeof(Dictionary<String, int?>));
         //return ((object)response) as Dictionary<String, int?>;
         
       } catch (Exception ex) {
@@ -71,7 +74,7 @@ namespace io.swagger.Api {
       }
     }
     
-
+    
     /// <summary>
     /// Place an order for a pet 
     /// </summary>
@@ -95,10 +98,13 @@ namespace io.swagger.Api {
       
       // form parameters, if any
       
+      
+      _request.AddParameter("application/json", ApiInvoker.Serialize(Body), ParameterType.RequestBody);
+      
 
       try {
-        IRestResponse response = _client.Execute(_request);
-        return (Order) ApiInvoker.deserialize(response.Content, typeof(Order));
+        IRestResponse response = restClient.Execute(_request);
+        return (Order) ApiInvoker.Deserialize(response.Content, typeof(Order));
         //return ((object)response) as Order;
         
       } catch (Exception ex) {
@@ -111,7 +117,7 @@ namespace io.swagger.Api {
       }
     }
     
-
+    
     /// <summary>
     /// Find purchase order by ID For valid response try integer IDs with value &lt;= 5 or &gt; 10. Other values will generated exceptions
     /// </summary>
@@ -128,17 +134,18 @@ namespace io.swagger.Api {
 
       // path (url segment) parameters
       _request.AddUrlSegment("format", "json"); // set format to json by default
-      _request.AddUrlSegment("orderId", apiInvoker.ParameterToString(OrderId));
+      _request.AddUrlSegment("orderId", ApiInvoker.ParameterToString(OrderId));
       // query parameters, if any
       
       // header parameters, if any
       
       // form parameters, if any
       
+      
 
       try {
-        IRestResponse response = _client.Execute(_request);
-        return (Order) ApiInvoker.deserialize(response.Content, typeof(Order));
+        IRestResponse response = restClient.Execute(_request);
+        return (Order) ApiInvoker.Deserialize(response.Content, typeof(Order));
         //return ((object)response) as Order;
         
       } catch (Exception ex) {
@@ -151,7 +158,7 @@ namespace io.swagger.Api {
       }
     }
     
-
+    
     /// <summary>
     /// Delete purchase order by ID For valid response try integer IDs with value &lt; 1000. Anything above 1000 or nonintegers will generate API errors
     /// </summary>
@@ -168,17 +175,18 @@ namespace io.swagger.Api {
 
       // path (url segment) parameters
       _request.AddUrlSegment("format", "json"); // set format to json by default
-      _request.AddUrlSegment("orderId", apiInvoker.ParameterToString(OrderId));
+      _request.AddUrlSegment("orderId", ApiInvoker.ParameterToString(OrderId));
       // query parameters, if any
       
       // header parameters, if any
       
       // form parameters, if any
       
+      
 
       try {
         
-        _client.Execute(_request);
+        restClient.Execute(_request);
         return;
       } catch (Exception ex) {
         if(ex != null) {
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 dfbede38cfb..7ca6bd5b1fc 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
@@ -8,31 +8,33 @@ namespace io.swagger.Api {
   
   public class UserApi {
     string basePath;
-    private readonly ApiInvoker apiInvoker = ApiInvoker.GetInstance();
-    protected RestClient _client;
+    protected RestClient restClient;
 
     public UserApi(String basePath = "http://petstore.swagger.io/v2")
     {
       this.basePath = basePath;
-      _client = new RestClient(basePath);
+      this.restClient = new RestClient(basePath);
     }
 
-    public ApiInvoker getInvoker() {
-      return apiInvoker;
-    }
-
-    // Sets the endpoint base url for the services being accessed
-    public void setBasePath(string basePath) {
+    /// <summary>
+    /// Sets the endpoint base url for the services being accessed
+    /// </summary>
+    /// <param name="basePath"> Base URL
+    /// <returns></returns>
+    public void SetBasePath(string basePath) {
       this.basePath = basePath;
     }
 
-    // Gets the endpoint base url for the services being accessed
-    public String getBasePath() {
-      return basePath;
+    /// <summary>
+    /// Gets the endpoint base url for the services being accessed
+    /// <returns>Base URL</returns>
+    /// </summary>
+    public String GetBasePath() {
+      return this.basePath;
     }
 
     
-
+    
     /// <summary>
     /// Create user This can only be done by the logged in user.
     /// </summary>
@@ -56,10 +58,13 @@ namespace io.swagger.Api {
       
       // form parameters, if any
       
+      
+      _request.AddParameter("application/json", ApiInvoker.Serialize(Body), ParameterType.RequestBody);
+      
 
       try {
         
-        _client.Execute(_request);
+        restClient.Execute(_request);
         return;
       } catch (Exception ex) {
         if(ex != null) {
@@ -71,7 +76,7 @@ namespace io.swagger.Api {
       }
     }
     
-
+    
     /// <summary>
     /// Creates list of users with given input array 
     /// </summary>
@@ -95,10 +100,13 @@ namespace io.swagger.Api {
       
       // form parameters, if any
       
+      
+      _request.AddParameter("application/json", ApiInvoker.Serialize(Body), ParameterType.RequestBody);
+      
 
       try {
         
-        _client.Execute(_request);
+        restClient.Execute(_request);
         return;
       } catch (Exception ex) {
         if(ex != null) {
@@ -110,7 +118,7 @@ namespace io.swagger.Api {
       }
     }
     
-
+    
     /// <summary>
     /// Creates list of users with given input array 
     /// </summary>
@@ -134,10 +142,13 @@ namespace io.swagger.Api {
       
       // form parameters, if any
       
+      
+      _request.AddParameter("application/json", ApiInvoker.Serialize(Body), ParameterType.RequestBody);
+      
 
       try {
         
-        _client.Execute(_request);
+        restClient.Execute(_request);
         return;
       } catch (Exception ex) {
         if(ex != null) {
@@ -149,12 +160,12 @@ namespace io.swagger.Api {
       }
     }
     
-
+    
     /// <summary>
     /// Logs user into the system 
     /// </summary>
     /// <param name="Username">The user name for login</param>
-     /// <param name="Password">The password for login in clear text</param>
+    /// <param name="Password">The password for login in clear text</param>
     
     /// <returns></returns>
     public string  LoginUser (string Username, string Password) {
@@ -174,10 +185,11 @@ namespace io.swagger.Api {
       
       // form parameters, if any
       
+      
 
       try {
-        IRestResponse response = _client.Execute(_request);
-        return (string) ApiInvoker.deserialize(response.Content, typeof(string));
+        IRestResponse response = restClient.Execute(_request);
+        return (string) ApiInvoker.Deserialize(response.Content, typeof(string));
         //return ((object)response) as string;
         
       } catch (Exception ex) {
@@ -190,7 +202,7 @@ namespace io.swagger.Api {
       }
     }
     
-
+    
     /// <summary>
     /// Logs out current logged in user session 
     /// </summary>
@@ -213,10 +225,11 @@ namespace io.swagger.Api {
       
       // form parameters, if any
       
+      
 
       try {
         
-        _client.Execute(_request);
+        restClient.Execute(_request);
         return;
       } catch (Exception ex) {
         if(ex != null) {
@@ -228,7 +241,7 @@ namespace io.swagger.Api {
       }
     }
     
-
+    
     /// <summary>
     /// Get user by user name 
     /// </summary>
@@ -245,17 +258,18 @@ namespace io.swagger.Api {
 
       // path (url segment) parameters
       _request.AddUrlSegment("format", "json"); // set format to json by default
-      _request.AddUrlSegment("username", apiInvoker.ParameterToString(Username));
+      _request.AddUrlSegment("username", ApiInvoker.ParameterToString(Username));
       // query parameters, if any
       
       // header parameters, if any
       
       // form parameters, if any
       
+      
 
       try {
-        IRestResponse response = _client.Execute(_request);
-        return (User) ApiInvoker.deserialize(response.Content, typeof(User));
+        IRestResponse response = restClient.Execute(_request);
+        return (User) ApiInvoker.Deserialize(response.Content, typeof(User));
         //return ((object)response) as User;
         
       } catch (Exception ex) {
@@ -268,12 +282,12 @@ namespace io.swagger.Api {
       }
     }
     
-
+    
     /// <summary>
     /// Updated user This can only be done by the logged in user.
     /// </summary>
     /// <param name="Username">name that need to be deleted</param>
-     /// <param name="Body">Updated user object</param>
+    /// <param name="Body">Updated user object</param>
     
     /// <returns></returns>
     public void  UpdateUser (string Username, User Body) {
@@ -286,17 +300,20 @@ namespace io.swagger.Api {
 
       // path (url segment) parameters
       _request.AddUrlSegment("format", "json"); // set format to json by default
-      _request.AddUrlSegment("username", apiInvoker.ParameterToString(Username));
+      _request.AddUrlSegment("username", ApiInvoker.ParameterToString(Username));
       // query parameters, if any
       
       // header parameters, if any
       
       // form parameters, if any
       
+      
+      _request.AddParameter("application/json", ApiInvoker.Serialize(Body), ParameterType.RequestBody);
+      
 
       try {
         
-        _client.Execute(_request);
+        restClient.Execute(_request);
         return;
       } catch (Exception ex) {
         if(ex != null) {
@@ -308,7 +325,7 @@ namespace io.swagger.Api {
       }
     }
     
-
+    
     /// <summary>
     /// Delete user This can only be done by the logged in user.
     /// </summary>
@@ -325,17 +342,18 @@ namespace io.swagger.Api {
 
       // path (url segment) parameters
       _request.AddUrlSegment("format", "json"); // set format to json by default
-      _request.AddUrlSegment("username", apiInvoker.ParameterToString(Username));
+      _request.AddUrlSegment("username", ApiInvoker.ParameterToString(Username));
       // query parameters, if any
       
       // header parameters, if any
       
       // form parameters, if any
       
+      
 
       try {
         
-        _client.Execute(_request);
+        restClient.Execute(_request);
         return;
       } catch (Exception ex) {
         if(ex != null) {
diff --git a/samples/client/petstore/csharp/src/main/csharp/io/swagger/Model/Category.cs b/samples/client/petstore/csharp/src/main/csharp/io/swagger/Model/Category.cs
index bfe1c0c4be8..7b13e16523a 100644
--- a/samples/client/petstore/csharp/src/main/csharp/io/swagger/Model/Category.cs
+++ b/samples/client/petstore/csharp/src/main/csharp/io/swagger/Model/Category.cs
@@ -2,21 +2,22 @@ using System;
 using System.Text;
 using System.Collections;
 using System.Collections.Generic;
+using System.Runtime.Serialization;
 
 namespace io.swagger.Model {
+  [DataContract]
   public class Category {
     
-
     
+    [DataMember(Name="id", EmitDefaultValue=false)]
     public long? Id { get; set; }
 
     
-
     
+    [DataMember(Name="name", EmitDefaultValue=false)]
     public string Name { get; set; }
 
     
-
     public override string ToString()  {
       var sb = new StringBuilder();
       sb.Append("class Category {\n");
@@ -31,4 +32,4 @@ namespace io.swagger.Model {
   }
   
   
-}
\ No newline at end of file
+}
diff --git a/samples/client/petstore/csharp/src/main/csharp/io/swagger/Model/Order.cs b/samples/client/petstore/csharp/src/main/csharp/io/swagger/Model/Order.cs
index 20a6d7367dd..3d67de0a82b 100644
--- a/samples/client/petstore/csharp/src/main/csharp/io/swagger/Model/Order.cs
+++ b/samples/client/petstore/csharp/src/main/csharp/io/swagger/Model/Order.cs
@@ -2,42 +2,42 @@ using System;
 using System.Text;
 using System.Collections;
 using System.Collections.Generic;
+using System.Runtime.Serialization;
 
 namespace io.swagger.Model {
+  [DataContract]
   public class Order {
     
-
     
+    [DataMember(Name="id", EmitDefaultValue=false)]
     public long? Id { get; set; }
 
     
-
     
+    [DataMember(Name="petId", EmitDefaultValue=false)]
     public long? PetId { get; set; }
 
     
-
     
+    [DataMember(Name="quantity", EmitDefaultValue=false)]
     public int? Quantity { get; set; }
 
     
-
     
+    [DataMember(Name="shipDate", EmitDefaultValue=false)]
     public DateTime ShipDate { get; set; }
 
     
-
     /* Order Status */
-    
+    [DataMember(Name="status", EmitDefaultValue=false)]
     public string Status { get; set; }
 
     
-
     
+    [DataMember(Name="complete", EmitDefaultValue=false)]
     public bool? Complete { get; set; }
 
     
-
     public override string ToString()  {
       var sb = new StringBuilder();
       sb.Append("class Order {\n");
@@ -60,4 +60,4 @@ namespace io.swagger.Model {
   }
   
   
-}
\ No newline at end of file
+}
diff --git a/samples/client/petstore/csharp/src/main/csharp/io/swagger/Model/Pet.cs b/samples/client/petstore/csharp/src/main/csharp/io/swagger/Model/Pet.cs
index b0f3573b78c..a00f8729d3f 100644
--- a/samples/client/petstore/csharp/src/main/csharp/io/swagger/Model/Pet.cs
+++ b/samples/client/petstore/csharp/src/main/csharp/io/swagger/Model/Pet.cs
@@ -2,42 +2,42 @@ using System;
 using System.Text;
 using System.Collections;
 using System.Collections.Generic;
+using System.Runtime.Serialization;
 
 namespace io.swagger.Model {
+  [DataContract]
   public class Pet {
     
-
     
+    [DataMember(Name="id", EmitDefaultValue=false)]
     public long? Id { get; set; }
 
     
-
     
+    [DataMember(Name="category", EmitDefaultValue=false)]
     public Category Category { get; set; }
 
     
-
     
+    [DataMember(Name="name", EmitDefaultValue=false)]
     public string Name { get; set; }
 
     
-
     
+    [DataMember(Name="photoUrls", EmitDefaultValue=false)]
     public List<string> PhotoUrls { get; set; }
 
     
-
     
+    [DataMember(Name="tags", EmitDefaultValue=false)]
     public List<Tag> Tags { get; set; }
 
     
-
     /* pet status in the store */
-    
+    [DataMember(Name="status", EmitDefaultValue=false)]
     public string Status { get; set; }
 
     
-
     public override string ToString()  {
       var sb = new StringBuilder();
       sb.Append("class Pet {\n");
@@ -60,4 +60,4 @@ namespace io.swagger.Model {
   }
   
   
-}
\ No newline at end of file
+}
diff --git a/samples/client/petstore/csharp/src/main/csharp/io/swagger/Model/Tag.cs b/samples/client/petstore/csharp/src/main/csharp/io/swagger/Model/Tag.cs
index 2fbf7070050..b0c08431472 100644
--- a/samples/client/petstore/csharp/src/main/csharp/io/swagger/Model/Tag.cs
+++ b/samples/client/petstore/csharp/src/main/csharp/io/swagger/Model/Tag.cs
@@ -2,21 +2,22 @@ using System;
 using System.Text;
 using System.Collections;
 using System.Collections.Generic;
+using System.Runtime.Serialization;
 
 namespace io.swagger.Model {
+  [DataContract]
   public class Tag {
     
-
     
+    [DataMember(Name="id", EmitDefaultValue=false)]
     public long? Id { get; set; }
 
     
-
     
+    [DataMember(Name="name", EmitDefaultValue=false)]
     public string Name { get; set; }
 
     
-
     public override string ToString()  {
       var sb = new StringBuilder();
       sb.Append("class Tag {\n");
@@ -31,4 +32,4 @@ namespace io.swagger.Model {
   }
   
   
-}
\ No newline at end of file
+}
diff --git a/samples/client/petstore/csharp/src/main/csharp/io/swagger/Model/User.cs b/samples/client/petstore/csharp/src/main/csharp/io/swagger/Model/User.cs
index 146ba13c768..37931c6fbe4 100644
--- a/samples/client/petstore/csharp/src/main/csharp/io/swagger/Model/User.cs
+++ b/samples/client/petstore/csharp/src/main/csharp/io/swagger/Model/User.cs
@@ -2,52 +2,52 @@ using System;
 using System.Text;
 using System.Collections;
 using System.Collections.Generic;
+using System.Runtime.Serialization;
 
 namespace io.swagger.Model {
+  [DataContract]
   public class User {
     
-
     
+    [DataMember(Name="id", EmitDefaultValue=false)]
     public long? Id { get; set; }
 
     
-
     
+    [DataMember(Name="username", EmitDefaultValue=false)]
     public string Username { get; set; }
 
     
-
     
+    [DataMember(Name="firstName", EmitDefaultValue=false)]
     public string FirstName { get; set; }
 
     
-
     
+    [DataMember(Name="lastName", EmitDefaultValue=false)]
     public string LastName { get; set; }
 
     
-
     
+    [DataMember(Name="email", EmitDefaultValue=false)]
     public string Email { get; set; }
 
     
-
     
+    [DataMember(Name="password", EmitDefaultValue=false)]
     public string Password { get; set; }
 
     
-
     
+    [DataMember(Name="phone", EmitDefaultValue=false)]
     public string Phone { get; set; }
 
     
-
     /* User Status */
-    
+    [DataMember(Name="userStatus", EmitDefaultValue=false)]
     public int? UserStatus { get; set; }
 
     
-
     public override string ToString()  {
       var sb = new StringBuilder();
       sb.Append("class User {\n");
@@ -74,4 +74,4 @@ namespace io.swagger.Model {
   }
   
   
-}
\ No newline at end of file
+}
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 ee2c5b1d889..abdfad1ae3b 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
@@ -1,235 +1,81 @@
-  using System;
-  using System.Collections.Generic;
-  using System.IO;
-  using System.Linq;
-  using System.Net;
-  using System.Text;
-  using Newtonsoft.Json;
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Net;
+using System.Text;
+using Newtonsoft.Json;
 
-  namespace io.swagger.client {
-    public class ApiInvoker {
-      private static readonly ApiInvoker _instance = new ApiInvoker();
-      private Dictionary<String, String> defaultHeaderMap = new Dictionary<String, String>();
+namespace io.swagger.client {
+  public class ApiInvoker {
+    private static Dictionary<String, String> defaultHeaderMap = new Dictionary<String, String>();
 
-      public static ApiInvoker GetInstance() {
-        return _instance;
-      }
+    /// <summary>
+    /// Add default header
+    /// </summary>
+    /// <param name="key">  Header field name
+    /// <param name="value"> Header field value
+    /// <returns></returns>
+    public static void AddDefaultHeader(string key, string value) {
+       defaultHeaderMap.Add(key, value);
+    }
 
-      /// <summary>
-      /// Add default header
-      /// </summary>
-      /// <param name="key">  Header field name
-      /// <param name="value"> Header field value
-      /// <returns></returns>
-      public void addDefaultHeader(string key, string value) {
-         defaultHeaderMap.Add(key, value);
-      }
+    /// <summary>
+    /// Get default header
+    /// </summary>
+    /// <returns>Dictionary of default header</returns>
+    public static Dictionary<String, String> GetDefaultHeader() {
+       return defaultHeaderMap;
+    }
 
-      /// <summary>
-      /// escape string (url-encoded)
-      /// </summary>
-      /// <param name="str"> String to be escaped
-      /// <returns>Escaped string</returns>
-      public string escapeString(string str) {
-        return str;
-      }
+    /// <summary>
+    /// escape string (url-encoded)
+    /// </summary>
+    /// <param name="str"> String to be escaped
+    /// <returns>Escaped string</returns>
+    public static string EscapeString(string str) {
+      return str;
+    }
 
-      /// <summary>
-      /// if parameter is DateTime, output in ISO8601 format, otherwise just return the string
-      /// </summary>
-      /// <param name="obj"> The parameter (header, path, query, form)
-      /// <returns>Formatted string</returns>
-      public string ParameterToString(object obj)
+    /// <summary>
+    /// if parameter is DateTime, output in ISO8601 format, otherwise just return the string
+    /// </summary>
+    /// <param name="obj"> The parameter (header, path, query, form)
+    /// <returns>Formatted string</returns>
+    public static string ParameterToString(object obj)
+    {
+      return (obj is DateTime) ? ((DateTime)obj).ToString ("u") : Convert.ToString (obj);
+    }
+
+    /// <summary>
+    /// Deserialize the JSON string into a proper object
+    /// </summary>
+    /// <param name="json"> JSON string
+    /// <param name="type"> Object type
+    /// <returns>Object representation of the JSON string</returns>
+    public static object Deserialize(string json, Type type) {
+      try
       {
-        return (obj is DateTime) ? ((DateTime)obj).ToString ("u") : Convert.ToString (obj);
+          return JsonConvert.DeserializeObject(json, type);
       }
-
-      /// <summary>
-      /// Deserialize the JSON string into a proper object
-      /// </summary>
-      /// <param name="json"> JSON string
-      /// <param name="type"> Object type
-      /// <returns>Object representation of the JSON string</returns>
-      public static object deserialize(string json, Type type) {
-        try
-        {
-            return JsonConvert.DeserializeObject(json, type);
-        }
-        catch (IOException e) {
-          throw new ApiException(500, e.Message);
-        }
-
+      catch (IOException e) {
+        throw new ApiException(500, e.Message);
       }
+    }
 
-      public static string serialize(object obj) {
-        try
-        {
-            return obj != null ? JsonConvert.SerializeObject(obj) : null;
-        }
-        catch (Exception e) {
-          throw new ApiException(500, e.Message);
-        }
-      }
-
-      public string invokeAPI(string host, string path, string method, Dictionary<String, String> queryParams, object body, Dictionary<String, String> headerParams, Dictionary<String, object> formParams)
+    /// <summary>
+    /// Serialize an object into JSON string
+    /// </summary>
+    /// <param name="obj"> Object 
+    /// <returns>JSON string</returns>
+    public static string Serialize(object obj) {
+      try
       {
-          return invokeAPIInternal(host, path, method, false, queryParams, body, headerParams, formParams) as string;
+          return obj != null ? JsonConvert.SerializeObject(obj) : null;
       }
-
-      public byte[] invokeBinaryAPI(string host, string path, string method, Dictionary<String, String> queryParams, object body, Dictionary<String, String> headerParams, Dictionary<String, object> formParams)
-      {
-          return invokeAPIInternal(host, path, method, true, queryParams, body, headerParams, formParams) as byte[];
-      }
-
-      private object invokeAPIInternal(string host, string path, string method, bool binaryResponse, Dictionary<String, String> queryParams, object body, Dictionary<String, String> headerParams, Dictionary<String, object> formParams) {
-        var b = new StringBuilder();
-
-        foreach (var queryParamItem in queryParams)
-        {
-            var value = queryParamItem.Value;
-            if (value == null) continue;
-            b.Append(b.ToString().Length == 0 ? "?" : "&");
-            b.Append(escapeString(queryParamItem.Key)).Append("=").Append(escapeString(value));
-        }
-
-        var querystring = b.ToString();
-
-          host = host.EndsWith("/") ? host.Substring(0, host.Length - 1) : host;
-
-          var client = WebRequest.Create(host + path + querystring);
-          client.Method = method;
-
-          byte[] formData = null;
-          if (formParams.Count > 0)
-          {
-              string formDataBoundary = String.Format("----------{0:N}", Guid.NewGuid());
-              client.ContentType = "multipart/form-data; boundary=" + formDataBoundary;
-              formData = GetMultipartFormData(formParams, formDataBoundary);
-              client.ContentLength = formData.Length;
-          }
-          else
-          {
-              client.ContentType = "application/json";
-          }
-
-          foreach (var headerParamsItem in headerParams)
-          {
-              client.Headers.Add(headerParamsItem.Key, headerParamsItem.Value);
-          }
-          foreach (var defaultHeaderMapItem in defaultHeaderMap.Where(defaultHeaderMapItem => !headerParams.ContainsKey(defaultHeaderMapItem.Key)))
-          {
-              client.Headers.Add(defaultHeaderMapItem.Key, defaultHeaderMapItem.Value);
-          }
-
-          switch (method)
-          {
-              case "GET":
-                  break;
-              case "POST":
-              case "PATCH":
-              case "PUT":
-              case "DELETE":
-                  using (Stream requestStream = client.GetRequestStream())
-                  {
-                      if (formData != null)
-                      {
-                          requestStream.Write(formData, 0, formData.Length);
-                      }
-
-                      var swRequestWriter = new StreamWriter(requestStream);
-                      swRequestWriter.Write(serialize(body));
-                      swRequestWriter.Close();
-                  }
-                  break;
-              default:
-                  throw new ApiException(500, "unknown method type " + method);
-          }
-
-          try
-          {
-              var webResponse = (HttpWebResponse)client.GetResponse();
-              if (webResponse.StatusCode != HttpStatusCode.OK)
-              {
-                  webResponse.Close();
-                  throw new ApiException((int)webResponse.StatusCode, webResponse.StatusDescription);
-              }
-
-              if (binaryResponse)
-              {
-                  using (var memoryStream = new MemoryStream())
-                  {
-                      webResponse.GetResponseStream().CopyTo(memoryStream);
-                      return memoryStream.ToArray();
-                  }
-              }
-              else
-              {
-                  using (var responseReader = new StreamReader(webResponse.GetResponseStream()))
-                  {
-                      var responseData = responseReader.ReadToEnd();
-                      return responseData;
-                  }
-              }
-          }
-          catch(WebException ex)
-          {
-              var response = ex.Response as HttpWebResponse;
-              int statusCode = 0;
-              if (response != null)
-              {
-                  statusCode = (int)response.StatusCode;
-                  response.Close();
-              }
-              throw new ApiException(statusCode, ex.Message);
-          }
-      }
-
-      private static byte[] GetMultipartFormData(Dictionary<string, object> postParameters, string boundary)
-      {
-          Stream formDataStream = new System.IO.MemoryStream();
-          bool needsCLRF = false;
-
-          foreach (var param in postParameters)
-          {
-              // Thanks to feedback from commenters, add a CRLF to allow multiple parameters to be added.
-              // Skip it on the first parameter, add it to subsequent parameters.
-              if (needsCLRF)
-                  formDataStream.Write(Encoding.UTF8.GetBytes("\r\n"), 0, Encoding.UTF8.GetByteCount("\r\n"));
-
-              needsCLRF = true;
-
-              if (param.Value is byte[])
-              {
-                  string postData = string.Format("--{0}\r\nContent-Disposition: form-data; name=\"{1}\"; filename=\"{1}\"\r\nContent-Type: {2}\r\n\r\n",
-                      boundary,
-                      param.Key,
-                      "application/octet-stream");
-                  formDataStream.Write(Encoding.UTF8.GetBytes(postData), 0, Encoding.UTF8.GetByteCount(postData));
-
-                  // Write the file data directly to the Stream, rather than serializing it to a string.
-                  formDataStream.Write((param.Value as byte[]), 0, (param.Value as byte[]).Length);
-              }
-              else
-              {
-                  string postData = string.Format("--{0}\r\nContent-Disposition: form-data; name=\"{1}\"\r\n\r\n{2}",
-                      boundary,
-                      param.Key,
-                      param.Value);
-                  formDataStream.Write(Encoding.UTF8.GetBytes(postData), 0, Encoding.UTF8.GetByteCount(postData));
-              }
-          }
-
-          // Add the end of the request.  Start with a newline
-          string footer = "\r\n--" + boundary + "--\r\n";
-          formDataStream.Write(Encoding.UTF8.GetBytes(footer), 0, Encoding.UTF8.GetByteCount(footer));
-
-          // Dump the Stream into a byte[]
-          formDataStream.Position = 0;
-          byte[] formData = new byte[formDataStream.Length];
-          formDataStream.Read(formData, 0, formData.Length);
-          formDataStream.Close();
-
-          return formData;
+      catch (Exception e) {
+        throw new ApiException(500, e.Message);
       }
     }
   }
+}