很简单,我做过,不需要Copy,不管你是用什么方法生成Excel(生成方法就不用说了吧),你每次生成用覆盖的方法把原来的覆盖掉保存到服务器一个权限够大(权限设置很重要)的文件夹中,下面代码是下载,注意把代码放在Try...Catch中
FileInfo fileInfo = new FileInfo(strPath);//strPath文件路径
Response.Clear();
Response.ClearContent();
Response.ClearHeaders();
Response.AddHeader("Content-Disposition", "attachment;filename=result.xls");
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();