Control objects can contain other objects, but, unlike container objects, do not allow access to the objects contained within them. For example, if you create a control object that consists of two ListBoxes and two CommandButtons, and then add the control object to a form, the ListBoxes and CommandButtons cannot be manipulated individually at design time or at run time.

For more information about control objects and how they differ from other objects and controls, see Object-Oriented Programming.