文件下载

 
    
         //下载文件
      public  void  DownLoad(string url){
         url=ConvertServerPath(url);   
         string filePath =Server.MapPath(url);
         FileInfo   fileinfo =new FileInfo ();
         Response.Clear();
         Response.ClearContent();
         Response.ClearHeaders();
         Response.AddHeader("Content-Disposition","attachment;filename"+fileInfo.Name);
         Response.AddHeader("Content-Length", fileInfo.Length.ToString());
         Response.AddHeader("Content-Transfer-Encoding", "binary");
         Response.ContentType = "application/octet-stream";
         Response.ContentEncoding = System.Text.Encoding.GetEncoding("gb2312");
         Response.WriteFile(fileinfo.FullName);
         Response.Flush();
         Response.End();

      }

     
    //转换成网站路径
     public  string  ConvertServerPath(string url){
     string  mapPath =HttpContext.Current.Server.MapPath(HttpContext.Current.Request.ApplicationPath.ToString()); //系统根路径
     string  xdPath=url.Replace(mapPath,"~"); //网站路径
     xdPath=xdpath.Replace(@"",@"/");
     return xdPath;
}

 
       //上传文件
      
       public   void   UpLoad(FileUpload   upload){
           if(upload.HasFile){  //存在文件
                if(upload.PostedFile.ContentLength< 100000){  //判断文件大小
                      string fullName =upload.PostedFile.FileName; //获取文件全称
                      string fileName =fullName.Substring(fullName.LastIndexOf("\")+1); //获取文件全称
                      string serverpath=Server.MapPath("~//File//")+fileName;   //存放到服务器路径
                      upload.PostedFile.SaveAs(serverpath);
                   }
               }
        
       }