public async Task <ActionResult> AddItemJson(string id, int quantity = 1) { await _cartBuilder.GetOrCreateNewTransientCartAsync(WorkContext.CurrentStore, WorkContext.CurrentCustomer, WorkContext.CurrentLanguage, WorkContext.CurrentCurrency); var product = await _catalogService.GetProductAsync(id, Model.Catalog.ItemResponseGroup.ItemLarge); if (product != null) { await _cartBuilder.AddItemAsync(product, quantity); await _cartBuilder.SaveAsync(); } return(Json(null, JsonRequestBehavior.AllowGet)); }