WriteFile实现下载

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/aaa.zip");          Response.TransmitFile(filename);      }

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

string fileName ="aaa.zip";//客户端保存的文件名         string filePath=Server.MapPath("DownLoad/aaa.zip");//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();      }

//WriteFile分块下载     protected void Button3_Click(object sender, EventArgs e)      {

string fileName = "aaa.zip";//客户端保存的文件名         string filePath = Server.MapPath("DownLoad/aaa.zip");//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();          }      }

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

}