弹出下载对话框

 #region 弹出下载对话框
        /// <summary>
        /// 打开指定的文件
        /// </summary>
        /// <param name="PathName">路径（相对路径）</param>
        /// <param name="FileName">文件名（带扩展名）</param>
        public static void OpenFile(string PathName, string FileName)
        {
            string name = PathName + FileName;
            FileInfo aFile = new FileInfo(System.Web.HttpContext.Current.Server.MapPath(name));
            string na = Path.GetFileName(name);
            System.Web.HttpContext.Current.Response.Clear();
            System.Web.HttpContext.Current.Response.ClearHeaders();
            System.Web.HttpContext.Current.Response.BufferOutput = false;
            System.Web.HttpContext.Current.Response.ContentType = "application/octet-stream";
            System.Web.HttpContext.Current.Response.AppendHeader("Content-disposition", "attachment;filename=" + System.Web.HttpContext.Current.Server.UrlDecode("你说的房间.zip"));
            System.Web.HttpContext.Current.Response.AddHeader("Content-Length", aFile.Length.ToString());
            System.Web.HttpContext.Current.Response.WriteFile(name);
            System.Web.HttpContext.Current.Response.Flush();
            System.Web.HttpContext.Current.Response.End();
        }
        #endregion 弹出下载对话框