By default, the DisplayExpandButton property is True. The DisplayExpandButton property displays the header's expanding button, only, if it contains child columns specified using the ExpandColumns property. The HasButtons property indicates the way the +/- ( expanding button ) is shown. Use the DisplayExpandButton property on True and ExpandColumns property to display the columns on multiple levels. The Expanded property expands programmatically a column. The control fires the LayoutChanged event when the user expands or collapse a column. Use the ExpandItem property to expand or collapse an item. The Index property indicates the column's index. The Visible property specifies whether a column is Visible or hidden.