private void btnLocCanBo_Click(object sender, EventArgs e)
{
dtGiaoVien = oBNS_GiaoVien.LocGiaoVien(cmbDonVi.EditValue == null ? 0 : int.Parse(cmbDonVi.EditValue.ToString()), txtHoTen.Text.Trim());
grdGiaoVien.DataSource = dtGiaoVien;
}