public void Add(string inventoryItem)
        {
            var InventoryItems = Request.Cookies["InventoryItems"];

            if (InventoryItems == null)
            {
                HttpCookie Inventory = SessionInformation.CreateCookie("InventoryItems", inventoryItem);
                Response.Cookies.Add(Inventory);
            }
            else
            {
                InventoryItems.Value = InventoryItems.Value + "+" + inventoryItem;
                Response.Cookies.Add(InventoryItems);
            }
        }