文件下载

//TransmitFile实现下载 
     protected void Button1_Click(object sender, EventArgs e)
    {
        Response.ContentType = "application/x-zip-compressed";
        Response.AddHeader("Content-Disposition", "attachment;filename=z.zip");
        string filename = Server.MapPath("DownLoad/z.zip");
        Response.TransmitFile(filename);
    }
 
     //WriteFile实现下载 
     protected void Button2_Click(object sender, EventArgs e)
    {
        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();
    }
 
     //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();
      }
  }
 
     //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.ReadAllBytes(FilePath));//---------　WebForm.Response.End();