//下载
string filePath = Server.MapPath("../Temp/" + ofname);//路径
FileInfo fileInfo = new FileInfo(filePath);
Response.Clear();
Response.ClearContent();
Response.ClearHeaders();
Response.AppendHeader("Content-Disposition", "attachment; filename="" + Server.UrlEncode(ofname) + """);//防止中文名出乱码,不过文件名中的空格会被“+”代替
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();