public ActionResult RemoveProduct(int productId = 0)
        {
            var cart = GetCart();

            CartHandler.ChangeProductCount(productId, 0, cart);
            var member = PublicUser.GetCurrentUser();

            if (member == null || member.MemberId <= 0)
            {
                Session[Constants.CartKeyName] = cart;
            }
            return(Json(new { Success = true }, JsonRequestBehavior.AllowGet));
        }