protected override void Edit(System.Windows.Forms.CurrencyManager source, int rowNum, System.Drawing.Rectangle bounds, bool readOnly, string instantText, bool cellIsVisible)
{
// Setup the ComboBox for action.
// This includes positioning the ComboBox and showing it.
// Also select the correct item in the ComboBox before it is shown.
combobox.Parent = this.DataGridTableStyle.DataGrid;
combobox.Bounds = bounds;
combobox.Size = new Size(this.Width, this.comboBox.Height);
comboBox.SelectedValue = base.GetColumnValueAtRow(source, rowNum).ToString();
combobox.Visible = (cellIsVisible == true) && (readOnly == false);
combobox.BringToFront();
combobox.Focus();
}