private void TrPhong_Load(object sender, EventArgs e)
{
Phong phong = new Phong();
SqlCommand command = new SqlCommand("Select * from TTKH ");
dataGridViewKH.ReadOnly = true;
dataGridViewKH.DataSource = phong.getshowkh(command);
dataGridViewKH.AllowUserToAddRows = false;
comboBox1.DataSource = phong.getAllTraPhong();;
comboBox1.DisplayMember = "MaKH";
comboBox1.ValueMember = "MaKH";
comboBox1.SelectedItem = null;
}
