.NET实现FTP上传功能错误
我的前台代码如下: 
  <%@   Page   Language= "C# "   AutoEventWireup= "true "   CodeBehind= "FtpUpload.aspx.cs "   Inherits= "MyInterface.UseFtp.FtpUpload "   %>    
  <!DOCTYPE   html   PUBLIC    "-//W3C//DTD   XHTML   1.0   Transitional//EN "    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd ">    
  <html   xmlns= "http://www.w3.org/1999/xhtml "   >  
  <head   runat= "server ">  
              <title> Untitled   Page </title>  
  </head>  
  <body>  
              <form   id= "form1 "   runat= "server ">  
              <div>  
                          <input   id= "File1 "   runat= "server "   type= "file "   />  
                          <br   />  
                          <asp:Button   ID= "txtUpload "   runat= "server "   OnClick= "txtUpload_Click "   Text= "上传 "   />  
                          <asp:Label   ID= "lblP "   runat= "server ">  </asp:Label>  </div>  
              </form>  
  </body>  
  </html>  
 主要是一个上传控件用来得到用户上传的文件路径. 
 一个提交按钮 
 后台代码如下: 
 using   System; 
 using   System.Data; 
 using   System.Configuration; 
 using   System.Collections; 
 using   System.Web; 
 using   System.Web.Security; 
 using   System.Web.UI; 
 using   System.Web.UI.WebControls; 
 using   System.Web.UI.WebControls.WebParts; 
 using   System.Web.UI.HtmlControls; 
 using   System.Net; 
 using   System.IO;   
 namespace   MyInterface.UseFtp 
 { 
             public   partial   class   FtpUpload   :   System.Web.UI.Page 
             { 
                         //ftp服务器IP 
                         string   ftpServerIP   =   ConfigurationSettings.AppSettings[ "ftpServerIP "]; 
                         //ftp用户名 
                         string   ftpUserID   =   ConfigurationSettings.AppSettings[ "ftpUserID "]; 
                         //ftp用户密码 
                         string   ftpPassword   =   ConfigurationSettings.AppSettings[ "ftpPassword "]; 
                         protected   void   Page_Load(object   sender,   EventArgs   e) 
                         {   
                         } 
                         ///    <summary>  
                         ///   利用FTP上传 
                         ///   by   minjiang   07-09-05 
                         ///    </summary>  
     &