Example of using IEnumerable as a property

gistfile1.txt

public class Order
{
    private List<OrderItem> items = new List<OrderItems>();
    
    public IEnumerable<OrderItem> Items
    {
        get { return items.Take(int.MaxValue); }
    }
}

public class Cheater
{
    public void Test()
    {
        var someOrder = new Order();
        // This will no longer work.
        ((List<OrderItem>)someOrder.Items).Add(new OrderItem());
        
        // This will not (because ToList creates a copy)
        someOrder.Items.ToList().Add(new OrderItem());
    }
}