Enumerating Windows/Controls of another application from .Net

Question

I'm developing a small utility application that needs to detect whether another one has one of its MDI child windows open (it's an off-the-shelf Win32 business application over which I have neither source code nor control). From my app, I would like to be able to poll or detect when a particular MDI Child window is open.

In .Net, it's easy to iterate over running processes, but I haven't found an easy way to iterate through the (sub)windows and controls of a given Win32 process from .Net.

Any ideas?

Update
Thanks for the answers they got me on the right path.
I found an article with a test project that uses both EnumWindowsand EnumChidWindows and other API calls to get extended information on controls.

Answer 1

You can use P/Invoke to access EnumWindows and EnumChidWindows to itereate through the subwindows/controls of any window.