asp.net 下载文件出有关问题了

asp.net 下载文件出问题了
先上代码：
                Response.Clear();
                Response.ClearContent();
                Response.ClearHeaders();
                Response.ContentType = "application/x-excel";
                Response.AddHeader("Content-Disposition", "attachment;filename=" + filename);
                string path = Server.MapPath("download") + "\" + filename;
                if (File.Exists(path))
                {
                    Response.TransmitFile(path);
                    Response.Flush(); 
                    Response.end(); 
                }
                else
                {
                    //找不到文件
                }
我在download里有一个内容为空的excel，写了这段做代码，运行测试下载文件，结果下载出来文件里面全部是网页里面内容（例如一些控件等等），按常理来说，下载的文件内容应该是空的，为什么会这样子？ 下载
[解决办法]
Refer:
http://www.cnblogs.com/insus/articles/2003336.html
[解决办法]
 Response.TransmitFile(path);

先将文件写入memoryStream
Response.WriteBinary（memoryStream。toarray）
试试
[解决办法]
                    Response.TransmitFile(path);
                    Response.Flush(); 
                    Response.end(); 
你这里是输出二进制流,完全看不出
            using (FileStream fso = new FileStream(Server.MapPath(DownAdress), FileMode.Open,FileAccess.ReadWrite,FileShare.Inheritable))
            {
                string[] filename=DownAdress.Split(new char[]{'/'});
                int len = Convert.ToInt32(fso.Length);
                byte[] FileObj = new byte[len];

                fso.Read(FileObj, 0, len);
                Response.AddHeader("Content-Disposition", string.Format("attachment; filename={0}", HttpUtility.UrlEncode(filename[filename.Length - 1]), System.Text.Encoding.UTF8));
                Response.AddHeader("Content-Length", len.ToString());
                Response.ContentType = "application/octet-stream";
                Response.Charset = "UTF-8";
                Response.ContentEncoding = System.Text.Encoding.UTF8; 
                Response.BinaryWrite(FileObj);
                Response.Flush();
                Response.Clear();
                fso.Close();
            }