private void btnThemMoi_ItemClick(object sender, DevExpress.XtraBars.ItemClickEventArgs e)
{
frmThemMoiHocSinh frm = new frmThemMoiHocSinh();
frm.ShowDialog();
HienThiThongTinHS();
}
private void btnCapNhatTT_ItemClick(object sender, DevExpress.XtraBars.ItemClickEventArgs e)
{
string MaHS = "";
MaHS = "" + gridThongTin.CurrentRow.Cells[3].Value;
frmThemMoiHocSinh frm = new frmThemMoiHocSinh();
frm.MaHS = MaHS;
frm.ShowDialog();
}