// GET: Admin/ProductItem/Edit/5
        public async Task <ActionResult> Edit(int?itemId, int?productId)
        {
            if (itemId == null || productId == null)
            {
                return(new HttpStatusCodeResult(HttpStatusCode.BadRequest));
            }
            ProductItem productItem = await GetProductItem(itemId, productId);

            if (productItem == null)
            {
                return(HttpNotFound());
            }
            return(View(await productItem.ConvertAsync(db)));
        }