.net中下载文件的方法(转)

.net中下载文件的方法

一、//TransmitFile实现下载      protected void Button1_Click(object sender, EventArgs e)      {          /*          微软为Response对象提供了一个新的方法TransmitFile来解决使用Response.BinaryWrite          下载超过400mb的文件时导致Aspnet_wp.exe进程回收而无法成功下载的问题。          代码如下：          */          Response.ContentType = "application/x-zip-compressed";          Response.AddHeader("Content-Disposition", "attachment;filename=z.zip");          string filename = Server.MapPath("DownLoad/z.zip");          Response.TransmitFile(filename);      }

二、//WriteFile实现下载      protected void Button2_Click(object sender, EventArgs e)      {          /*          using System.IO;

         */          string fileName = "asd.txt";//客户端保存的文件名          string filePath = Server.MapPath("DownLoad/aaa.txt");//路径

         FileInfo fileInfo = new FileInfo(filePath);          Response.Clear();          Response.ClearContent();          Response.ClearHeaders();          Response.AddHeader("Content-Disposition", "attachment;filename=" + fileName);          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();      }

三、    //WriteFile分块下载      protected void Button3_Click(object sender, EventArgs e)      {          string fileName = "aaa.txt";//客户端保存的文件名          string filePath = Server.MapPath("DownLoad/aaa.txt");//路径

         System.IO.FileInfo fileInfo = new System.IO.FileInfo(filePath);

         if (fileInfo.Exists == true)          {              const long ChunkSize = 102400;//100K 每次读取文件，只读取100K，这样可以缓解服务器的压力              byte[] buffer = new byte[ChunkSize];

             Response.Clear();              System.IO.FileStream iStream = System.IO.File.OpenRead(filePath);              long dataLengthToRead = iStream.Length;//获取下载的文件总大小              Response.ContentType = "application/octet-stream";              Response.AddHeader("Content-Disposition", "attachment; filename=" + HttpUtility.UrlEncode(fileName));              while (dataLengthToRead > 0 && Response.IsClientConnected)              {                  int lengthRead = iStream.Read(buffer, 0, Convert.ToInt32(ChunkSize));//读取的大小                  Response.OutputStream.Write(buffer, 0, lengthRead);                  Response.Flush();                  dataLengthToRead = dataLengthToRead - lengthRead;              }              Response.Close();          }      }

四、//流方式下载      protected void Button4_Click(object sender, EventArgs e)      {          string fileName = "aaa.txt";//客户端保存的文件名          string filePath = Server.MapPath("DownLoad/aaa.txt");//路径

         //以字符流的形式下载文件          FileStream fs = new FileStream(filePath, FileMode.Open);          byte[] bytes = new byte[(int)fs.Length];          fs.Read(bytes, 0, bytes.Length);          fs.Close();          Response.ContentType = "application/octet-stream";          //通知浏览器下载文件而不是打开          Response.AddHeader("Content-Disposition", "attachment; filename=" + HttpUtility.UrlEncode(fileName, System.Text.Encoding.UTF8));          Response.BinaryWrite(bytes);          Response.Flush();          Response.End();      }

//----------------------------------------------------------

public void DownloadFile( System.Web.UI.Page WebForm,String FileNameWhenUserDownload ,String FileBody ) {

　　WebForm.Response.ClearHeaders(); 　　WebForm.Response.Clear(); 　　WebForm.Response.Expires = 0; 　　WebForm.Response.Buffer = true; 　　WebForm.Response.AddHeader("Accept-Language", "zh-tw"); 　　//'文件名称 　　WebForm.Response.AddHeader("content-disposition", "attachment; filename='"+System.Web.HttpUtility.UrlEncode(FileNameWhenUserDownload, System.Text.Encoding.UTF8)+"'"); 　　WebForm.Response.ContentType = "Application/octet-stream"; 　　//'文件内容 　　WebForm.Response.Write(FileBody);//-----------      WebForm.Response.End(); }

//上面这段代码是下载一个动态产生的文本文件，若这个文件已经存在于服务器端的实体路径，则可以通过下面的函数：

public void DownloadFileByFilePath( System.Web.UI.Page WebForm,String FileNameWhenUserDownload ,String FilePath ) { 　　WebForm.Response.ClearHeaders(); 　　WebForm.Response.Clear(); 　　WebForm.Response.Expires = 0;      WebForm.Response.Buffer = true; 　　WebForm.Response.AddHeader("Accept-Language", "zh-tw"); 　　//文件名称 　　WebForm.Response.AddHeader("content-disposition", "attachment; filename='" + System.Web.HttpUtility.UrlEncode(FileNameWhenUserDownload, System.Text.Encoding.UTF8) +"'" ); 　　WebForm.Response.ContentType = "Application/octet-stream"; 　　//文件内容 　　WebForm.Response.Write(System.IO.File.Rea}dAllBytes(FilePath));//--------- 　　WebForm.Response.End();

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