public HomeController(IValueCalculator calcParam)
        {
            calc = calcParam;
        }

        public ActionResult Index()
        {
            ShoppingCart cart = new ShoppingCart(calc)
            {
                Products = products
            };
            decimal totalValue = cart.CalculateProductTotal();
            return View(totalValue);
        }

public ShoppingCart(LinqValueCalculator calcParam)

    public class LinqValueCalculator : IValueCalculator