public override bool AddGiftItem(int giftId, int quantity)
        {
            XmlDocument shoppingCartData = this.GetShoppingCartData();
            XmlNode     xmlNode          = shoppingCartData.SelectSingleNode("//sc/gf");
            XmlNode     xmlNode2         = xmlNode.SelectSingleNode("l[@g=" + giftId + "]");

            if (xmlNode2 == null)
            {
                xmlNode2 = CookieShoppingData.CreateGiftLineItemNode(shoppingCartData, giftId, quantity);
                xmlNode.InsertBefore(xmlNode2, xmlNode.FirstChild);
            }
            else
            {
                xmlNode2.Attributes["q"].Value = (int.Parse(xmlNode2.Attributes["q"].Value) + quantity).ToString(CultureInfo.InvariantCulture);
            }
            this.SaveShoppingCartData(shoppingCartData);
            return(true);
        }