private void buttonX2_Click(object sender, EventArgs e)
        {
            frmDocGia ft = new frmDocGia();

            ft.Show();
            this.Hide();
        }
 private void buttonX2_Click(object sender, EventArgs e)
 {
     frmDocGia ft = new frmDocGia();
     ft.Show();
     this.Hide();
 }