private void btnThem_Click(object sender, EventArgs e)
{
frmThemPhong frm = new frmThemPhong();
frm.ShowDialog();
loadDuLieu();
}
private void toolStripButton2_Click(object sender, EventArgs e)
{
frmThemPhong f = new frmThemPhong();
this.Hide();
f.ShowDialog();
this.Show();
LoadData(dataGridView2, "Phong");
}