excle直接以某个文件名保存到指定文件夹

从DS导出数据到Excel,无需打开Excel,直接填充并分配文件名保存到指定路径文件夹...    --------------------编程问答-------------------- 帮帮忙啊
--------------------编程问答-------------------- Excel中不是有个SaveAs的方法啊,直接调用就可以了啊 --------------------编程问答--------------------         string strFullFileName = Server.MapPath("." + "/tset.xls");
        FileInfo DownloadFile = new FileInfo(strFullFileName);
        Response.Clear();
        Response.ClearHeaders();
        Response.Buffer = false;
        Response.ContentType = "application/vnd.ms-excel";
        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(); --------------------编程问答--------------------         Response.Charset = "GB2312";
        Response.ContentEncoding = Encoding.UTF7;
        Response.AppendHeader("Content-Disposition", "attachment;filename=" + HttpUtility.UrlEncode(strFileName + ".xls", Encoding.UTF8).ToString());//
        Response.ContentType = "application/ms-excel";
        this.EnableViewState = false;
        StringWriter tw = new StringWriter();
        HtmlTextWriter hw = new HtmlTextWriter(tw);
        gridview1.RenderControl(hw);//
        Response.Write(tw.ToString());
        Response.End(); --------------------编程问答-------------------- 可能我没说清楚，excle是没有生成的，就是说将未生成的excle以某一名字保存到文件夹

补充：.NET技术 ,  ASP.NET