文件下载

 private void DownLoad(string filename)
    {

        FileInfo DownloadFile = new FileInfo(filename);
        Response.Clear();
        Response.ClearHeaders();
        Response.Buffer = false;

        Response.AddHeader("Content-Type", "application/PDF");
        Response.AppendHeader("Content-Disposition", "attachment;filename=" + HttpUtility.UrlEncode(DownloadFile.FullName, System.Text.Encoding.UTF8));
        Response.AppendHeader("Content-Length", DownloadFile.Length.ToString());
        Response.WriteFile(DownloadFile.FullName);
        Response.Flush();
        Response.End();


    }