Based on class that has no key defined mvc5

Question

I try to add view from this controller . I only need this view to show data not for insert or update or delete ``` public ActionResult Index() { var CartObj = ShoppingCart.GetCart(this.HttpContext); var classshop = new New { CartItems = CartObj.GetCartItems(), CartTotal = CartObj.GetSum() }; return View(classshop); } namespace MusicStore.Models { public class ShoppingCart { MusicStoreEntities dbo = new MusicStoreEntities(); string ShoppingCartID { get; set; } public const string CartSessionKey = "CartId"; public static ShoppingCart GetCart(HttpContextBase Context) { var cart = new ShoppingCart(); cart.ShoppingCartID = cart.GetCardId(Context); return cart; } public static ShoppingCart GetCart(Controller controller) { return GetCart(controller.HttpContext); } public List<Cart> GetCartItems() { return dbo.Carts.Where(a => a.CartId == ShoppingCartID).ToList(); } public decimal? GetSum() { decimal? Sum = (from items in dbo.Carts where items.CartId == ShoppingCartID select (int)items.Count…

Accepted Answer

There are two options here. First, if this class is mapped to a table in your database, every model in entity framework requires a primary key. Add this into your model:

```
[Key]
public int Id { get; set; }
```

This creates a new property called `Id` and the `[Key]` attribute makes it a primary key. Technically you don't need the attribute as EF will pick up `Id` property and use it as a key, but I prefer to be explicit.

Alternatively, if you don't want this class to be a table in your database, add the `NotMapped` attribute to the class like this:

```
[NotMapped]
public class New
{
    public List<Cart> CartItems { get; set; }
    public decimal? CartTotal { get; set; }

}
```

Based on class that has no key defined mvc5

Solution

Problem