Forms have two parts: a visible part and an invisible part. The visible part is what you see on the
screen. The invisible part holds the form's variables.
When you use Unload to unload a form, the visible part is destroyed but the invisible part is not.
If you redisplay the form, its variables have the same values they did when you unloaded the form.
To clear the form's variables, set the reference to the form object to Nothing. Do this even if you
are using the special instance of the form named after itself, even though that doesn't seem to make sense.
Later you can use the special instance variable to redisplay the form with reset values.