public void ChangeBillingAddress(int cartId, Address address) { var service = new Core.ShoppingCartService(_context.Instance); var cart = service.Find(cartId); _context.Database.Transactional(() => { var addr = GetOrCreateAddress(cart.Customer.Id, address); if (address.Id == 0) { address.Id = addr.Id; } service.ChangeBillingAddress(cart, addr); }); }