public IActionResult OnPostPlus(int id)
{
CartItems = HttpContext.Session.GetObjectFromJson <List <ShoppingCart> >("CartItems").ToList();
var productiInCart = CartItems.SingleOrDefault(x => x.Product.Id == id);
var cartItemPlus = cartBL.PlusCartItem(productiInCart);
CartItems
.Where(x => x.Id == id)
.Select(x => { x.Quantity = cartItemPlus.Quantity; return(x); }).ToList();
if (cartItemPlus.Quantity == productiInCart.Product.Quantity)
{
TempData["Message"] = $"You have reached the limit for {productiInCart.Product.Name}!";
}
HttpContext.Session.SetObjectAsJson("CartItems", CartItems);
CartItems = HttpContext.Session.GetObjectFromJson <List <ShoppingCart> >("CartItems").ToList();
return(RedirectToPage("./ShoppingCart"));
}