public IActionResult OnGetBuy(int id)
{
var product = productData.GetProductById(id);
if (HttpContext.Session.GetObjectFromJson <List <ShoppingCart> >("CartItems") != null)
{
CartItems = HttpContext.Session.GetObjectFromJson <List <ShoppingCart> >("CartItems").ToList();
var productiInCart = CartItems.SingleOrDefault(x => x.Product.Id == id);
if (CartItems.Contains(productiInCart))
{
return(RedirectToPage("./ShoppingCart"));
}
}
CartItems.Add(cartBL.AddCartItem(product));
HttpContext.Session.SetObjectAsJson("CartItems", CartItems);
CartItems = HttpContext.Session.GetObjectFromJson <List <ShoppingCart> >("CartItems").ToList();
return(RedirectToPage("./ShoppingCart"));
//return Page();
}