private void btnUserLogin_Click(object sender, EventArgs e)
        {
            this.Hide();
            FormUserLogin form2 = new FormUserLogin();

            form2.ShowDialog();
        }
        private void button1_Click(object sender, EventArgs e)
        {
            int i = shopping.m_customerID;

            using (conn)
            {
                conn.Open();
                using (SqlCommand cmd = new SqlCommand("DELETE FROM ShoppingCart " + "WHERE CustomerId=@Id", conn))
                {
                    cmd.Parameters.AddWithValue("@Id", i);
                    int rows = cmd.ExecuteNonQuery();
                }
            }

            user.watch.Stop();
            MessageBox.Show("Time spent on the system: " + user.watch.Elapsed.Seconds + " seconds", "Time stamp");

            this.Hide();
            FormUserLogin formlog = new FormUserLogin();

            formlog.ShowDialog();
            conn.Close();
        }