string name = Server.MapPath( " 文件名 " ).Replace( " / " , " / " ).Trim();FileStream fileStream = new FileStream(name, FileMode.Open); long fileSize = fileStream.Length;Context.Response.ContentType = " application/octet-stream " ;Context.Response.AddHeader( " Content-Disposition " , " attachment; filename=" " + HttpUtility.UrlEncode( " 下载时默认的文件名 " , System.Text.Encoding.UTF8) + " " " );Context.Response.AddHeader( " Content-Length " , fileSize.ToString()); byte [] fileBuffer = new byte [fileSize];fileStream.Read(fileBuffer, 0 , ( int )fileSize);fileStream.Close();Response.BinaryWrite(fileBuffer);Response.End(); 参考文章: http://blog.joycode.com/uestc95/archive/2004/05/25/22494.aspx http://dev.wl668.com/net/ASP/20051135202_4199288.shtml