asp.net 下载功能出错？？？~~

[xingxingsuhuan]

System.IO.FileInfo file = new System.IO.FileInfo(filepath);
Response.Clear();
Response.AddHeader("Content-Disposition", "attachment;filename=" + file.Name);
Response.AddHeader("Content-Length", file.Length.ToString());
Response.ContentType = "application/octet-stream";
Response.WriteFile(file.FullName);
Response.End();

Response.Flush();
Response.Clear();

执行到Response.End(); 弹出对话框说：无法复制文件：无法读源文件或磁盘。
调试filepath路径是正确

[cppfaq]

去掉这句呢？
Response.End();