public ActionResult RemoveFromCart(int id)
        {
            //Remove the item from the cart
            var cart = ShoppingCart.GetCart(this.HttpContext);

            //Get the name of the item to display confirmation

            //Get the name of the album to display confirmation
            string itemName = db.tb_producto
                .Single(item => item.id_producto == id).nombre_prod;

            //Remove from cart
            int itemCount = cart.RemoveFromCart(id);

            //Display the confirmation message
            var results = new ShoppingCartRemoveViewModel
            {
                Message = "One (1) " + Server.HtmlEncode(itemName) +
                    " ha sido eliminado de su carrito.",
                CartTotal = cart.GetTotal(),
                CartCount = cart.GetCount(),
                ItemCount = itemCount,
                DeleteId = id
            };
            return Json(results);
        }
        public ActionResult AddToCart(int id)
        {
            // Retrieve the item from the database
            var addedItem = db.tb_producto
                .Single(item => item.id_producto == id);

            // Add it to the shopping cart
            var cart = ShoppingCart.GetCart(this.HttpContext);

            int count = cart.AddToCart(addedItem);

            // Display the confirmation message
            var results = new ShoppingCartRemoveViewModel
            {
                Message = Server.HtmlEncode(addedItem.nombre_prod) +
                    " has been added to your shopping cart.",
                CartTotal = cart.GetTotal(),
                CartCount = cart.GetCount(),
                ItemCount = count,
                DeleteId = id
            };
            return Json(results);
        }