EnableGroupboxControls is a function I have used in several projects, where I wanted to enable/disable all the controls within a groupbox. There are several other solutions to this problem here on CodeProject - I have included a list here. None of these, however, had everything I was looking for: Able to be used in MFC or non-MFC project - since I spend a lot of time maintaining older Windows applications, I wanted a very lightweight solution.

Able to be used without instantiating class - this was important, because I necessarily have to minimize the impact on existing code.

Able to be used without recoding or redefining existing control variables - again, for same reasons as previous point.

Able to accommodate nested groupboxes - many of the dialogs in apps I maintain are non-trivial, because the apps themselves are highly technical. Nesting groupboxes is one way of coping with complex user interfaces.