public ActionResult AddToCart(int productId) { string userId = User.Identity.GetUserId(); ApplicationUserIdentity user = userAppService.FindByID(userId); CartProduct cartProduct = new CartProduct() { CartID = user.Id, ProductID = productId, Quantity = 1 }; cartAppService.addProduct(cartProduct); TempData["Msg_Cart"] = "New Item Added Successfully To Cart"; return(RedirectToAction("index")); }