System.InvalidCastException: Razor View

Question

When I debug my project, and add an item to cart I am thrown this error, not sure what to do?

System.InvalidCastException: 'Unable to cast object of type 'System.Collections.Generic.List1[ShoppingCartApp.Classes.CartItem]' to type 'System.Collections.Generic.List1[ShoppingCartApp.Controllers.CartItem]'.'

The error is thrown on this line @foreach (CartItem cartItem in (List<CartItem>)Session["shoppingCart"]) in my view

Heres my controller

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using ShoppingCartApp.ServiceReference1;
using ShoppingCartApp.Classes;

public class ShoppingCartController : Controller
    {
        Service1Client wcf = new Service1Client(); // Connection to WCF

        // GET: ShoppingCart
        public ActionResult ShoppingCart()
        {
            return View("ShoppingCart");
        }

        private int checkIfExisting(int id) // Checks session for existing products, increases quantity if product exists
        {
            List<CartItem> shoppingCart = (List<CartItem>)Session["shoppingCart"];
            for (int x = 0; x < shoppingCart.Count; x++)
                if (shoppingCart[x].Product.ProductID == id)
                    return x;
            return -1;
        }

        public ActionResult RemoveFromCart(int id)
        {
            List<CartItem> shoppingCart = new List<CartItem>();
            shoppingCart.Remove(new CartItem(wcf.GetProduct(id), 1));
            Session["shoppingCart"] = shoppingCart;
            return View("ShoppingCart");
        }


        public ActionResult AddToCart(int id) // Creates new session if one is not existing, adds item to cart, uses checkifexisting method to increase quantity
        {

            if(Session["shoppingCart"] == null)
            {
                List<CartItem> shoppingCart = new List<CartItem>();
                shoppingCart.Add(new CartItem(wcf.GetProduct(id), 1));
                Session["shoppingCart"] = shoppingCart;
            } else

            {
                List<CartItem> shoppingCart = (List <CartItem>)Session["shoppingCart"];
                int index = checkIfExisting(id);
                if (index == -1)
                    shoppingCart.Add(new CartItem(wcf.GetProduct(id), 1));
                else
                    shoppingCart[index].Quantity++;
                Session["shoppingCart"] = shoppingCart;
            }
            return View("ShoppingCart");
        }

        public ActionResult Checkout()
        {
            OrderDetail orderDetail = wcf.GetOrderDetail();
            return View();
        }
    }

And heres the class

    using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using ShoppingCartApp.ServiceReference1;

namespace ShoppingCartApp.Classes
{
    public class CartItem
    {

        private Product product = new Product();

        public Product Product
        {
            get { return product; }
            set { product = value; }
        }

        private int quantity;

        public int Quantity
        {
            get { return quantity; }
            set { quantity = value; }
        }


        public CartItem(Product product, int quantity)
        {
            this.product = product;
            this.Quantity = quantity;
        }
    }
}

What exactly is it telling me to do?

Answer 1

in my view I changed ShoppingCartApp.Controllers to ShoppingCartApp.Classes, which resolved the issue completely