private void CellClicked(object sender, DataGridViewCellEventArgs e)
        {
            try
            {
                if (e.ColumnIndex >= 0 &&
                     codeGroupGrid.Columns[e.ColumnIndex] == editButtonColumn)
                {
                    CodeGroup group = groupBindingSource.Current as CodeGroup;
                    EditForm form = new EditForm(group);
                    form.ShowInTaskbar = false;

                    form.StartPosition = FormStartPosition.CenterParent;
                    form.ShowDialog(ParentForm);
                }
            }
            catch (Exception ex)
            {
                Utilities.HandleException(ex);
            }
        }