Specifies a Choice Action's item collection.
A ChoiceActionItemCollection object that represents a collection of a Choice Action's items.
The ChoiceActionItemCollection contains items that can, themselves, contain a collection of items. So, you can specify a tree of items for the current Choice Action. For this purpose, use the Items property. The most convenient way to specify this property is to use the Properties window, where an ellipsis button is attached to this property. Alternatively, you can do it in code (see Add an Action with Option Selection).
To detect if the Items collection is tree-like, use the ChoiceActionBase.IsHierarchical method.