asp.net中用户下载一个已存在的附件

1.vs2003中下载一个存在的文件
   string filename = "Templete.xls";
   System.IO.FileInfo info = new System.IO.FileInfo(Server.MapPath("./")  + filename);
   Response.AddHeader("content-type", "application/ms-excel");
   Response.AddHeader("content-length", info.Length.ToString());
   Response.AddHeader("content-disposition", "attachment;filename=" + filename + "");
   Response.WriteFile(Server.MapPath("./")  + filename);

 

2.vs2005中的下载一个已存在文件
 string path = Server.MapPath("readme.txt");
        //下载文件的名称
        string filename = "readme.txt";
        System.IO.FileInfo toDownload = new System.IO.FileInfo(path);
        Response.Clear();
        if (System.IO.Path.GetExtension(filename) == ".txt") //可以根据不同的文件类型设置不同的ContentType
        {
            Response.AddHeader("Content-Disposition", "attachment;filename=NEW_" + HttpUtility.UrlEncode(toDownload.Name));
            Response.ContentType = "text/plain";
            Response.TransmitFile(path);
            Response.End();
        }