/// 
        /// Web请求方式：1、Get 2、Post        /// 
        public enum RequestMethod        {            Get,            Post        }

　　

/// 
        /// 保存图片        /// 
        ///         /// 
             private static string SaveImage(HttpPostedFileBase uploadfile, string filePath)        {            string fileExtentsion = Path.GetExtension(uploadfile.FileName).ToLower();            string tmpFileName = Guid.NewGuid().ToString("N").ToLower() + fileExtentsion;            if (!Directory.Exists(filePath))            {                Directory.CreateDirectory(filePath);            }            string serverLocalPath = Path.Combine(filePath, tmpFileName);            uploadfile.SaveAs(serverLocalPath);            return serverLocalPath;        }

　　

/// 
        /// Web请求        /// 
        ///         ///         ///         /// 
             public static string Request(string url, RequestMethod method, Dictionary
     
       parameters)        {            UriBuilder URI = new UriBuilder(url);            HttpWebRequest webRequest = null;            Stream requestWriter = null;            string responseData = BuildQueryString(parameters);            URI.Query = responseData;            webRequest = System.Net.WebRequest.Create(URI.Uri) as HttpWebRequest;            webRequest.Method = method.ToString();            webRequest.ServicePoint.Expect100Continue = false;            byte[] data = Encoding.UTF8.GetBytes(responseData);            if (method == RequestMethod.Post)            {                webRequest.ContentType = "application/x-www-form-urlencoded";                requestWriter = webRequest.GetRequestStream();                try                {                    requestWriter.Write(data, 0, data.Length);                }                catch                {                    throw;                }                finally                {                    requestWriter.Close();                    requestWriter = null;                }            }            responseData = WebResponseGet(webRequest);            webRequest = null;            return responseData;        }
     

　　

/// 
        /// 当前请求转发至其他服务器（上传多张图片）        /// 
        ///         ///         ///         /// 
             public static string HttpUploadFileList(string url, RequestMethod method, Dictionary
     
       parameters, List
      
        uploadfileList)        {            string result = string.Empty;            string boundary = "---------------------------" + DateTime.Now.Ticks.ToString("x");            byte[] boundarybytes = Encoding.ASCII.GetBytes("\r\n--" + boundary + "\r\n");            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);            request.ContentType = "multipart/form-data; boundary=" + boundary;            request.Method = method.ToString();            request.KeepAlive = true;            request.Credentials = CredentialCache.DefaultCredentials;            Stream stream = request.GetRequestStream();            string template = "Content-Disposition: form-data; name=\"{0}\"\r\n\r\n{1}";            #region request.form 参数            foreach (string _key in parameters.Keys)            {                string value = Convert.ToString(parameters[_key]);                stream.Write(boundarybytes, 0, boundarybytes.Length);                string formitem = string.Format(template, _key, value);                byte[] formitembytes = Encoding.UTF8.GetBytes(formitem);                stream.Write(formitembytes, 0, formitembytes.Length);            }            #endregion            stream.Write(boundarybytes, 0, boundarybytes.Length);            #region 文件            foreach (HttpPostedFileBase uploadfile in uploadfileList)            {                stream.Write(boundarybytes, 0, boundarybytes.Length);                string headerTemplate = "Content-Disposition: form-data; name=\"{0}\"; filename=\"{1}\"\r\nContent-Type: {2}\r\n\r\n";                string header = string.Format(headerTemplate, "uploadfile", uploadfile.FileName, uploadfile.ContentType);                byte[] headerbytes = Encoding.UTF8.GetBytes(header);                stream.Write(headerbytes, 0, headerbytes.Length);                byte[] imageData = null;                using (BinaryReader binaryReader = new BinaryReader(uploadfile.InputStream))                {                    imageData = binaryReader.ReadBytes(uploadfile.ContentLength);                }                stream.Write(imageData, 0, imageData.Length);            }            #endregion            byte[] bytes = Encoding.ASCII.GetBytes("\r\n--" + boundary + "--\r\n");            stream.Write(bytes, 0, bytes.Length);            stream.Close();            result = WebResponseGet(request);            request = null;            return result;        }
      
     

　　

/// 
        /// 读取数据        /// 
        /// HttpWebRequest        /// 
     
      根据参数条件返回相应的数据
             private static string WebResponseGet(HttpWebRequest webRequest)        {            StreamReader responseReader = null;            string responseData = "";            try            {                responseReader = new StreamReader(webRequest.GetResponse().GetResponseStream());                responseData = responseReader.ReadToEnd();            }            catch            {                throw;            }            finally            {                webRequest.GetResponse().GetResponseStream().Close();                responseReader.Close();                responseReader = null;            }            return responseData;        }

　　

/// 
        /// 将Dictionary
      
       集合遍历成URL参数！        /// 
      
        /// Dictionary
     
      config        /// 
      
       Query
              public static string BuildQueryString(Dictionary
      
        config)        {            List
       
         paramList = new List
        
         ();            foreach (KeyValuePair
         
           item in config)            {                paramList.Add(string.Format("{0}={1}", item.Key, item.Value));            }            return string.Join("&", paramList.ToArray());        }
         
        
       
      
     

　　HttpClient发送数据：

public async Task
     
       Request (System.Net.Http.HttpMethod method, Dictionary
      
        keyValeDic, string url, HttpContent content)        {            using (HttpClient client = new HttpClient())            {                HttpRequestMessage request = new HttpRequestMessage();                request.Method = method;                request.RequestUri = new Uri(url);                request.Content = content;                if (keyValeDic != null)                {                    foreach(var keyVale in keyValeDic)                    {                        request.Headers.Add(keyVale.Key, keyVale.Value);                    }                }                if (content != null)                {                    client.DefaultRequestHeaders.Accept.Add(new System.Net.Http.Headers.MediaTypeWithQualityHeaderValue("application/json"));                    request.Content.Headers.ContentType = new System.Net.Http.Headers.MediaTypeHeaderValue("application/json");                }                // 毫秒转 TimeSpan                var milliseconds = 5 * 1000;//可配置                client.Timeout = TimeSpan.FromMilliseconds(milliseconds);                HttpResponseMessage responseMessage = await client.SendAsync(request);                string result = await responseMessage.Content.ReadAsStringAsync();                if (responseMessage.IsSuccessStatusCode)                {                    return result;                }                else                {                    return string.Empty;                }            }        }