Enabled when not visible?

What happens if the user clicks on an invisible command button?

If a control is not visible, is it enabled?

I sometimes want to prevent Command Button actions. I have been setting enabled to false, but think it would look better if the disaabled controls were invisible.

Should I set both visible and enabled to false?

In my experience, if a control is invisible, it won't receive messages from user interaction (mouse clicks, key presses, etc). But I guess there is no harm in doing both if you are worried.