private void FileDownload(string FullFileName)

　　{

　　FileInfo DownloadFile = new FileInfo(FullFileName);

　　Response.Clear();

　　Response.ClearHeaders();

　　Response.Buffer = false;

　　Response.ContentType = "application/octet-stream";

　　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();

　　}

　　调用方法

　　string path= Server.MapPath("fujian/"+文件名称);//path为服务器存放文件的路径

　　FileDownload(path);

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