public IActionResult SearchAndSort(string search, string sortorder, int?pagenumber)
        {
            pageNumber = pagenumber ?? 1;
            ViTriQuangcaoBUS     vitri    = new ViTriQuangcaoBUS();
            GoiQuangCaoBUS       goi      = new GoiQuangCaoBUS();
            List <GoiQuangCao>   list     = goi.SearchAndSort(search, sortorder, pageSize, pageNumber);
            List <GoiQuangCao>   tong     = goi.SearchAndSort(search, sortorder, pageSize);
            List <ViTriQuangcao> listvtqc = vitri.GetViTriQuangcaos();

            ViewBag.TrangHienTai  = pageNumber;
            ViewBag.TongTrang     = TongTrang(tong);
            ViewBag.ViTriQuangcao = listvtqc;
            ViewBag.TrangThai     = "searchandsort";
            ViewBag.Search        = search;
            ViewBag.Sort          = sortorder;
            return(View("Index", list));
        }