private void btnThem_Click(object sender, EventArgs e)
{
txtMaNCC.Text = ThucThiSQL.AutoGenerate2("NCC", "tblNCC");
txtMaNCC.ReadOnly = true;
txtTenNCC.Enabled = true;
txtDiachi.Enabled = true;
txtSDT.Enabled = true;
btnLuu.Enabled = true;
SemiReset();
}