>My form have quite a number of controls.
>Your idea should work fine if I have "exclude all other controls, get the listbox populated with values only if focus is about to be set to 1 or 2 controls" scenario.
>However, in my case, it is exactly the reverse scenario, I want to "do nothing" only for 1 or 2 controls and get the listbox populated with values for the rest of controls.
>
>If I were to do it as you have suggested, that means I will have to add code to GetFocus event of almost all controls in the form and I think I can easily forget about adding the same code, if in the future I need to add new control to the form.

Don't remember, can you bind the GotFocus event?