constants ShowAsButtonEnum
The ShowAsButtonEnum type specifies the way a button is shown. The ShowAsButton property specifies whether the current item is shown a button or a select button. The ShowAsButtonEnum type supports the following values:

NameValueDescription
exShowAsButtonNone0 No button is associated with the current item.
exShowAsButton1 A button is associated with the current item. This flag can be combined with exShowAsButtonAutoSize flag.

exShowAsButtonAutoSize2 The size of the button's caption fits the item's caption. This flag can be combined with any other flags.
exShowAsSelectButton17 A select button is associated with the current item ( show the drop-down button to the right ). The exShowAsSelectButton flag has effect only if the current item is a popup item, so it contains sub-items. The SubMenu property gives access to the item's sub menu, while it is a popup item. The Add(Caption,SubMenu) adds a popup item. The item's SubMenu is shown bellow the button, when user clicks the associated arrow. The popup being shown is a local popup, so clicking any item inside a local popup makes the popup itself to close including all its descendent sub-menus, without closing any ascendant sub-menus. 

exShowAsSelectButtonBottom273 A select button is associated with the current item ( show the drop-down button to the bottom ). The exShowAsSelectButtonBottom flag has effect only if the current item is a popup item, so it contains sub-items. The SubMenu property gives access to the item's sub menu, while it is a popup item. The Add(Caption, SubMenu) adds a popup item ( an item that contains sub-items ). The item's SubMenu is shown bellow the button, when user clicks the associated arrow. The popup being shown is a local popup, so clicking any item inside a local popup makes the popup itself to close including all its descendent sub-menus, without closing any ascendant sub-menus.