protected void CartRepeater_ItemCommand(object source, RepeaterCommandEventArgs e)
    {
        CartManager manager = new CartManager(this.Cart);

        if (e.CommandName == "AddCoupon")
        {
            TextBox OfferCodeTextBox = CartRepeater.Controls[CartRepeater.Controls.Count - 1].FindControl("OfferCodeTextBox") as TextBox;
            if (OfferCodeTextBox == null)
            {
                return;
            }
            Coupon coupon = Coupons.GetCoupon(OfferCodeTextBox.Text);
            if (coupon.CouponID > 0)
            {
                try
                {
                    manager.AddCoupon(coupon);
                    CouponMessageLiteral.Text = "Offer added to cart";
                }
                catch (Exception ex)
                {
                    CouponMessageLiteral.Text = ex.Message;
                }
            }
            else
            {
                CouponMessageLiteral.Text = "Offer Code not found.";
            }
        }
        else
        {
            manager.Remove(e.Item.ItemIndex);
        }
        DeleteSavedCart();
        this.Cart = manager.ShoppingCart;
        BindCart();
    }