Issue with EnumWindows

Question

When enumerating windows using EnumWindows, I get hundreds of handles instead of one per open window on my desktop.

First of all, i am curious if this is the correct behavior.

Secondly, trying to get a difference between open windows before and after launching a process returns 15-20 new handles. I am wondering if there is a way to filter these based on some flag, i really need just the mainwindow handle.

Any ideas?

Answer 1

To get the main window of a process, use the Process.MainWindowHandle property.

To answer your question, you can see exactly what all of the handles are using Spy++.
In short, many applications will create hidden windows to run message loops.

Answer 2

You can filter within the enum callback by checking IsWindowVisible() & ignoring invisible system/message sink windows.