Delphi, how to programmatically press a key in someone else's window knowing the handle of the window?

Question

Delphi

Hello, I've been sitting for hours looking for information on how to press a key in someone else's window (for example, F1) knowing the window handle. The problem is that FindWindow cannot find the window by its title.
How to proceed, what to do?

Answer 1

So FindWindow will actually return the Handle, since you already know it - what's the problem?
SendMessage takes the window Handle as the first parameter, the second you pass WM_KEYDOWN, the third - VK_F1

Answer 2

Why isn't it looking for it? We need to deal with this. Maybe you're looking for child window and need to use FindWindowEx? Or is the title of some wrong / wrong transfer?