I'm wondering how to get the content of a textbox or richtextbox control in ANOTHER process , given its handle.

I have made a program which seems to able to get the content from
simpler programs, like the textfield of notepad.exe and such,
but when I try other applications it doesnt work. The way
I'm currently getting the content is using the WM_GETTEXT
message with sendMessage API.

The type...