“Cross-thread operation not valid” exception on inner controls

Question

I\'ve been struggling with this for quite a while: I have a function designed to add control to a panel with cross-thread handling, the problem is that though the panel and

Answer 1

Where is pnlFoo being created, and in which thread? Do you know when its handle is being created? If it's being created in the original (non-UI) thread, that's the problem.

All control handles in the same window should be created and accessed on the same thread. At that point, you shouldn't need two checks for whether Invoke is required, because ctrl and panel should be using the same thread.

If this doesn't help, please provide a short but complete program to demonstrate the problem.