public ActionResult Product(int?page)
        {
            var pager     = new Pager(productService.getTotalRecord(), page);
            var viewModel = new ProductPagerViewModel
            {
                Products = productService.loadProduct(pager.CurrentPage, pager.PageSize),
                Pager    = pager
            };

            return(View(viewModel));
        }
        // GET: Admin/Product

        public ActionResult Index(int?page)
        {
            var userSession = (UserLogin)Session[CommonConstands.ADMIN_SESSION];

            if (userSession == null)
            {
                return(Redirect("~/Admin/Login/Login"));
            }

            var pager     = new Pager(productService.getTotalRecord(), page);
            var viewModel = new ProductPagerViewModel
            {
                Products = productService.loadProduct(pager.CurrentPage, pager.PageSize),
                Pager    = pager
            };

            return(View(viewModel));
        }