private void barButtonItem2_ItemClick(object sender, DevExpress.XtraBars.ItemClickEventArgs e)
        {
            if (!isViewExam)
            {
                return;
            }
            DataGridViewRow row = getListRowSelected(dgvContainerExam).FirstOrDefault();
            frmEditExam     frm = new frmEditExam(row);

            frm.ShowDialog();
            LoadData(pageIndex);
        }
        private void barButtonItem4_ItemClick(object sender, DevExpress.XtraBars.ItemClickEventArgs e)
        {
            frmEditExam frm = new frmEditExam();

            frm.ShowDialog();
            if (dgvContainerExam.Visible)
            {
                LoadData(pageIndex);
            }
            else
            {
                btnListExam.PerformClick();
            }
        }