Your going about this the wrong way, don't change the edit's size inside it's own proc. Change it inside your main window's proc. Also, when msg is WM_SIZE, lParam contains the new window dimensions (So you don't have to call GetClientRect).
Your going about this the wrong way, don't change the edit's size inside it's own proc. Change it inside your main window's proc. Also, when msg is WM_SIZE, lParam contains the new window dimensions (So you don't have to call GetClientRect).