public ActionResult SelectProductInv(ProductVM p, int Quantity)
        {
            if (Quantity == 0)
            {
                Quantity = 1;
            }
            int?    x  = HttpContext.Session.GetInt32("Product id");
            Product p2 = _strBL.SelectProduct((int)x);

            p2.quantity += Quantity;
            int y = p2.quantity;

            Debug.WriteLine(p2.id);
            _strBL.UpdateInventory(p2);
            HttpContext.Session.SetInt32("newQuantity", y);
            HttpContext.Session.SetInt32("oldQuantity", Quantity);
            return(View("Updated"));
        }