asp.net 下载已二进制存在数据库中的文件

Response.ContentType = "application/octet-stream";
                        //通知浏览器下载文件而不是打开
                        Response.AddHeader("Content-Disposition", "attachment; filename=" + HttpUtility.UrlEncode(model.Zlbt+"."+model.Zlhz, System.Text.Encoding.UTF8));
                        Response.BinaryWrite(model.Zlwj);
                        Response.Flush();
                        Response.End();

model.Zlbt：文件名

model.Zlhz:文件后缀