public Cart GetPromotion()
 {
     Cart promotionCart = new Cart();
     for (int count = 0; count < this.Cart.CartList.Length; count++)
     {
         Product promotionProduct = this.Cart.CartList[count];
         for (int position = 0; position < ShopInformation.CurrentPromotion.PromotionList.Length; position++)
         {
             if (promotionProduct == ShopInformation.CurrentPromotion.PromotionList[count])
             {
                 promotionProduct.Price = ShopInformation.CurrentPromotion.PromotionList[count].Price;
             }
         }
         promotionCart.AddProduct(promotionProduct);
     }
     return promotionCart;
 }
        public Cart GetPromotion(Cart currentCart)
        {
            Cart cart = new Cart();
            for (int position = 0; position < currentCart.CartList.Length; position++)
            {
                Product currentProduct = currentCart.CartList[position];
                for (int count = 0; count < promotionList.Length; count++)
                {
                    if (currentProduct == promotionList[count])
                    {
                        currentProduct.Price = promotionList[count].Price;
                    }
                }
                cart.AddProduct(currentProduct);
            }

            return cart;
        }