建立商品列表及新增商品、刪除商品Controller

public ActionResult ItemBlock(int Id)
        {
            ItemDetailView ViewData = new ItemDetailView();
            ViewData.Data = itemService.GetDataById(Id);
            string Cart = (HttpContext.Session["Cart"] != null)
                ? HttpContext.Session["Cart"].ToString() : null;
            ViewData.InCart = cartService.CheckInCart(Cart, Id);
            return PartialView(ViewData);
        }
        [Authorize(Roles = "Admin")] 
        public ActionResult Create()
        {
            return View();
        }
        [Authorize(Roles = "Admin")] 
        [HttpPost]
        public ActionResult Add(ItemCreateView Data)
        {
            if (Data.ItemImage != null)
            {
                string filename = Path.GetFileName(Data.ItemImage.FileName);
                string Url = Path.Combine(Server.MapPath("~/Upload/")
                    , filename);
                Data.ItemImage.SaveAs(Url);
                Data.NewData.Image = filename;
                itemService.Insert(Data.NewData);
                return RedirectToAction("Index");
            }
            else
            {
                ModelState.AddModelError("ItemImage", "請選擇上傳檔案");
                return View(Data);
            }
        }
        [Authorize(Roles = "Admin")] 
        public ActionResult Delete(int Id)
        {
            itemService.Delete(Id);
            return RedirectToAction("Index");
        }
    }