public FileResult Export(bool?privacy)
        {
            AdsStatisticsSearchModel search = Session["ExportSearch"] as AdsStatisticsSearchModel;

            if (search == null)
            {
                search = new AdsStatisticsSearchModel();
            }

            ViewData["Info"]               = AdvertisementStatisticsDAO.GetAll(search);
            ViewData["Privacy"]            = privacy ?? false;
            ViewData["AdsPositionMapping"] = AdvertisementStatisticsDAO.AdsPosition;

            string html = Utility.GetViewHtml(this, "Export", null);

            string title = $"廣告分析報表-{DateTime.Now.ToString("yyyyMMddHHmmsss")}.xls";

            return(File(System.Text.Encoding.UTF8.GetBytes(html), "application/vnd.ms-excel", title));
        }