[C#]
public class HierachyColumnWithImages : HierachyColumn
{
  private Image plusButton = null;
  [DefaultValue(null)]
  public Image PlusButton
  {
    get
    {
      return plusButton;
    }
    set
    {
      if (plusButton != value)
      {
        plusButton = value;
        base.OnChanged(InvalidationMode.ColumnWithoutHeader, false);
      }
    }
  }
  private Image minusButton = null;
  [DefaultValue(null)]
  public Image MinusButton
  {
    get
    {
      return minusButton;
    }
    set
    {
      if (minusButton != value)
      {
        minusButton = value;
        base.OnChanged(InvalidationMode.ColumnWithoutHeader, false);
      }
    }
  }
  protected override void DrawPlusMinusButton(CellDrawInfo dci, Rectangle rectangle, int xmiddle, int ymiddle)
  {
    Image button = dci.node.Expanded ?
      MinusButton != null ? MinusButton : null : PlusButton != null ? PlusButton : null;
    if (button != null)
    {
      dci.g.DrawImage(button, rectangle);
    }
    else
      base.DrawPlusMinusButton (dci, rectangle, xmiddle, ymiddle);
  }
}