Do edit boxes send messages when their text is changed the way a button does when it's clicked? If so, which one? And if not, do I have to subclass the edit box to find out when it's text is changed?
The parent gets a WM_COMMAND message, with LOWORD(wParam) as the notification and lParam as the handle of the edit control.
The two notifications you'll want to look at are:
EN_UPDATE - sent when the text is changed, but before it's re-displayed
EN_CHANGE - sent after the control has been re-drawn
Thanks.