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  • (总结3)WinForm中文件上传服务器:HttpWebRequest .

    因项目需要,要实现WinForm下的文件上传,个人觉得采用FTP方法太麻烦,还得配置FTP服务器,要通过防火墙也是一个麻烦。本来打算采用WebClient方法,但是采用这个方法实现后,进度条很短时间后就达到最大值,要等待一段时间才能传送完毕,要是文件太大(我这里测试约100M),会出现错误。后来才知道,原来WebClient是在加载完整个文件到内存后才真正开始上传,怪不得会出现前面的问题了。不得已参考了很多文章,老外的一个文章对我启发很大(http://blogs.msdn.com/johan/archive/2006/11/15/are-you-getting-outofmemoryexceptions-when-uploading-large-files.aspx),是采用HttpWebRequest方法实现的。废话少说,开始进入正题。实现过程如下:

    在WinForm里面调用下面的方法来上传文件:

    参数说明如下:

    address:接收文件的URL地址,如:http://localhost/UploadFile/Save.aspx

    fileNamePath:要上传的本地文件,如:D:/test.rar

    saveName:文件上传到服务器后的名称,如:200901011234.rar

    progressBar:显示文件上传进度的进度条。


      /// <summary>
      /// 将本地文件上传到指定的服务器(HttpWebRequest方法)
      /// </summary>
      /// <param name="address">文件上传到的服务器</param>
      /// <param name="fileNamePath">要上传的本地文件(全路径)</param>
      /// <param name="saveName">文件上传后的名称</param>
      /// <param name="progressBar">上传进度条</param>
      /// <returns>成功返回1,失败返回0</returns>
      public int UploadFile(string address, string fileNamePath, string saveName, ProgressBarControl progressBar)
      {
       int returnValue = 0;
       // 要上传的文件
       FileStream fs = new FileStream(fileNamePath, FileMode.Open, FileAccess.Read);
       BinaryReader r = new BinaryReader(fs);


       //时间戳
       string strBoundary = "----------" + DateTime.Now.Ticks.ToString("x");
       byte[] boundaryBytes = Encoding.ASCII.GetBytes("\r\n--" + strBoundary + "\r\n");


       //请求头部信息
       StringBuilder sb = new StringBuilder();
       sb.Append("--");
       sb.Append(strBoundary);
       sb.Append("\r\nContent-Disposition: form-data; name=\"file\"; filename=\"");
       sb.Append(saveName);
       sb.Append("\"\r\nContent-Type:  ");
       sb.Append("application/octet-stream");
       sb.Append("\r\n\r\n");
       string strPostHeader = sb.ToString();
       byte[] postHeaderBytes = Encoding.UTF8.GetBytes(strPostHeader);

       // 根据uri创建HttpWebRequest对象
       HttpWebRequest httpReq = (HttpWebRequest)WebRequest.Create(new Uri(address));
       httpReq.Method = "POST";

       //对发送的数据不使用缓存
       httpReq.AllowWriteStreamBuffering = false;
       //设置获得响应的超时时间(300秒)
       httpReq.Timeout = 300000;
       httpReq.ContentType = "multipart/form-data; boundary=" + strBoundary;
       long length = fs.Length + postHeaderBytes.Length + boundaryBytes.Length;
       long fileLength = fs.Length;
       httpReq.ContentLength = length;
       try
       {
                           progressBar.Properties.Maximum = int.MaxValue;
                           progressBar.Properties.Minimum = 0;
                           progressBar.EditValue = 0;

                           //每次上传4k 
                           int bufferLength = 4096;
                           byte[] buffer = new byte[bufferLength];

                           //已上传的字节数
                           long offset = 0;
                           //开始上传时间 
                           DateTime startTime = DateTime.Now;
                           int size = r.Read(buffer, 0, bufferLength);

                    using (Stream postStream = httpReq.GetRequestStream())
                    {
                            //发送请求头部消息
                            postStream.Write(postHeaderBytes, 0, postHeaderBytes.Length);
                            while (size > 0)
                            {
                             postStream.Write(buffer, 0, size);////文件的内容

                             offset += size;
                             progressBar.EditValue = (int)(offset * (int.MaxValue / length));
                             TimeSpan span = DateTime.Now - startTime;
                             double second = span.TotalSeconds;
                             lblTime.Text = "已用时:" + second.ToString("F2") + "秒";
                             if (second > 0.001)
                             {
                                     lblSpeed.Text = " 平均速度:" + (offset / 1024 / second).ToString("0.00") + "KB/秒";
                             }
                             else
                             {
                              lblSpeed.Text = " 正在连接…";
                             }
                             lblState.Text = "已上传:" + (offset * 100.0 / length).ToString("F2") + "%";
                             lblSize.Text = (offset / 1048576.0).ToString("F2") + "M/" + (fileLength / 1048576.0).ToString("F2") + "M";
                             System.Windows.Forms.Application.DoEvents();

                             size = r.Read(buffer, 0, bufferLength);
                            }
                            //添加尾部的时间戳 
                            postStream.Write(boundaryBytes, 0, boundaryBytes.Length);
                 }//postStream.Close();

               //获取服务器端的响应 
               WebResponse webRespon = httpReq.GetResponse();
               Stream s = webRespon.GetResponseStream();
               StreamReader sr = new StreamReader(s);
               //读取服务器端返回的消息
               String sReturnString = sr.ReadLine();
               s.Close();
               sr.Close();
               if (sReturnString == "Success")
               {
                     returnValue = 1;
               }
               else if (sReturnString == "Error")
               {
                     returnValue = 0;
               }
              }
              catch
              {
                       returnValue = 0;
              }
              finally
              {
                       fs.Close();
                       r.Close();
              }
              return returnValue;
             }

           调用:


      /// <summary>
      /// HttpWebRequest上传
      /// </summary>
      /// <param name="sender"></param>
      /// <param name="e"></param>
      private void btnUpload_Click(object sender, EventArgs e)
      {
       try
       {
        string iniPath = DataConvert.ToString(btnOpenDialog.EditValue);
        if (iniPath.Length == 0)
        {
         XtraMessageBox.Show("请选择要上传的文件!");
         return;
        }
        panelJD.Visible = true;
        
        string address = string.Format("{0}Save.aspx", Core.CoreOption.WsAddressErp); 

        int rst = UploadFile(address, iniPath, "dd.rar", progressBarControl1);

       }
       catch (Exception err)
       {
        XtraMessageBox.Show(err.Message);
       }
      }

    aspx文件:


      protected void Page_Load(object sender, EventArgs e)
      {
       // 在此处放置用户代码以初始化页面   
        try
        {
         if (Request.Files.Count > 0)
         {
          foreach (string f in Request.Files.AllKeys)
          {
           HttpPostedFile file = Request.Files[f];
           string filePath = @"D:\Temp\" + file.FileName;
           //string p= this.MapPath("test") + "//" + file.FileName;
           file.SaveAs(filePath);
           Response.Write("Success/r/n");
          }
         }
        }
        catch
        {
         Response.Write("Error/r/n");
        }
       
      }

    同时需要配置WebConfig文件的httpRuntime 如下:

    <httpRuntime maxRequestLength="102400"  executionTimeout="300"/>

    不能的话最大只能上传4M了。要是想上传更大的文件,maxRequestLength,executionTimeout设置大些,同时WinForm下的代码行

    //设置获得响应的超时时间(300秒)
                httpReq.Timeout = 300000;

    也要修改,另外别忘了看看IIS的连接超时是否设置为足够大。

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  • 原文地址:https://www.cnblogs.com/lovenan/p/2818229.html
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