1      /// <summary>
  2         /// 发起httpPost 请求，可以上传文件
  3         /// </summary>
  4         /// <param name="url">请求的地址</param>
  5         /// <param name="files">文件</param>
  6         /// <param name="input">表单数据</param>
  7         /// <param name="endoding">编码</param>
  8         /// <returns></returns>
  9         public static string PostResponse(string url, UpLoadFile[] files, Dictionary<string, string> input, Encoding endoding)
 10         {
 11 
 12             string boundary = "----------------------------" + DateTime.Now.Ticks.ToString("x");
 13             HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
 14             request.ContentType = "multipart/form-data; boundary=" + boundary;
 15             request.Method = "POST";
 16             request.KeepAlive = true;
 17             request.Credentials = CredentialCache.DefaultCredentials;
 18 
 19 
 20             MemoryStream stream = new MemoryStream();
 21 
 22             byte[] line = Encoding.ASCII.GetBytes("\r\n--" + boundary + "\r\n");
 23 
 24             //提交文本字段
 25             if (input != null)
 26             {
 27                 string format = "--" + boundary + "\r\nContent-Disposition:form-data;name=\"{0}\"\r\n\r\n{1}\r\n";    //自带项目分隔符
 28                 foreach (string key in input.Keys)                                                                    
 29                 {
 30                     string s = string.Format(format, key, input[key]);
 31                     byte[] data = Encoding.UTF8.GetBytes(s);
 32                     stream.Write(data, 0, data.Length);
 33                 }
 34            
 35             }
 36 
 37             ////提交文件
 38             if (files != null)
 39             {
 40              ;
 41                 string fformat = "Content-Disposition:form-data; name=\"{0}\"; filename=\"{1}\"\r\nContent-Type: {3}\r\n\r\n";
 42                 foreach (UpLoadFile file in files)
 43                 {
 44 
 45                     stream.Write(line, 0, line.Length);        //项目分隔符
 46                     string s = string.Format(fformat, file.Name, file.FileName, file.FileLength, file.Content_Type);
 47                     byte[] data = Encoding.UTF8.GetBytes(s);
 48                     stream.Write(data, 0, data.Length);
 49                     stream.Write(file.Data, 0, file.Data.Length);
 50                 }
 51             }
 52 
 53 
 54             byte[] foot_data = Encoding.UTF8.GetBytes("\r\n--" + boundary + "--\r\n");      //项目最后的分隔符字符串需要带上--  
 55             stream.Write(foot_data, 0, foot_data.Length);  
 56 
 57 
 58 
 59             request.ContentLength = stream.Length;
 60             Stream requestStream = request.GetRequestStream(); //写入请求数据
 61             stream.Position = 0L;
 62             stream.CopyTo(requestStream); //
 63             stream.Close();
 64 
 65             requestStream.Close();
 66 
 67 
 68 
 69             try
 70             {
 71 
 72 
 73                 HttpWebResponse response;
 74                 try
 75                 {
 76                     response = (HttpWebResponse)request.GetResponse();
 77 
 78                     try
 79                     {
 80                         using (var responseStream = response.GetResponseStream())
 81                         using (var mstream = new MemoryStream())
 82                         {
 83                             responseStream.CopyTo(mstream);
 84                             string message = endoding.GetString(mstream.ToArray());
 85                             return message;
 86                         }
 87                     }
 88                     catch (Exception ex)
 89                     {
 90                         throw ex;
 91                     }
 92                 }
 93                 catch (WebException ex)
 94                 {
 95                     response = (HttpWebResponse)ex.Response;
 96                    
 97       
 98                     if (response.StatusCode == HttpStatusCode.BadRequest)
 99                     {
100                         using (Stream data = response.GetResponseStream())
101                         {
102                             using (StreamReader reader = new StreamReader(data))
103                             {
104                                 string text = reader.ReadToEnd();
105                                 Console.WriteLine(text);
106                             }
107                         }
108                     }
109 
110                     throw ex;
111                 }
112 
113              
114             }
115             catch (Exception ex)
116             {
117                 throw ex;
118             }
119 
120         }