// GET: OrderDetails/Edit/5
        public async Task <IActionResult> Edit(int?id)
        {
            if (id == null)
            {
                return(NotFound());
            }

            var orderDetails = await orderDetailsRepository.FindAsync(id);

            if (orderDetails == null)
            {
                return(NotFound());
            }

            ViewData["ProductId"] = new SelectList(_context.Product, "Id", "Name");
            return(View(orderDetails));
        }
        public async Task <IActionResult> OnGetAsync(int?id)
        {
            if (id == null)
            {
                return(NotFound());
            }

            OrderDetails = await orderDetailsRepository.FindAsync(id);

            if (OrderDetails == null)
            {
                return(NotFound());
            }

            ViewData["OrderId"]   = new SelectList(await orderRepository.GetAllAsync(), "Id", "Id");
            ViewData["ProductId"] = new SelectList(await productRepository.GetAllProducts(), "Id", "Id");

            return(Page());
        }