protected virtual void ShowColumnCommandMenu(int columnIndex, Point pt)
{
ToolStripDropDown m = this.MakeColumnCommandMenu(new ContextMenuStrip(), columnIndex);
if (this.SelectColumnsOnRightClick) {
if (m.Items.Count > 0)
m.Items.Add(new ToolStripSeparator());
this.MakeColumnSelectMenu(m);
}
m.Show(pt);
}