how to know if window's text got change

hi,
I am writing monitoring application , which enum and save every handles which is running. by sending and reciving WM_GETTEXT messages i retrieve some information as well. Bu this process runs everytime even if text is not changed. Is there any way to trigger text extraction process if that specific windows get change.

Suppose if i am extracting aol text , then is there anyway to extract text only when data gets change otherwise leave it. I dont wana play with Strings to compare what was the last message but i need to find a way on event call of window change...

i hope i have cleared what ia m asking

thanks in advamce

You have to install a hook on the process that owns the window handle. You can then trap WM_SETTEXT message.

any other choice than hooking??

Not to my knowledge

Yes, the other method (WE) has been given many times on Win32 api ng, but not too old (1999)..

Laurentis, quite a few of your posts end up with referring to ng without giving a clue as to what to search for in there. So, your posts are utterly useless in that regard. This is a forum to help others help themselves , and with millions of posts searching itself can be a task in itself. If you know what keywords to search for , please post those also here, so your post really becomes helpful. For example, you say "other method (WE)". What does that mean. Are we supposed to search for keyword "other method" and "WE" ?

yes please if you know anything then describe little more so we can understand what your refering here ..

As kirants said, the windows hook is the eastest way.