Use the ExpandOnClick property to specify whether the control expands or collapses when the user clicks the group's caption. Use the DisplayExpandIcon property to show or hide the expand/collapse icons. Use the ExpandIcon property to specify the icons used for expanded/collapsed groups. Use the Expanded property to expand a group. The control fires the ExpandGroup event when the user clicks the group's caption. The control fires the SelectGroup event when the user clicks the caption of the group. Use the Caption property to specify the caption of the group. Use the AllowExpand property to disable expanding or collapsing a group.