Onload Validation?

How can I make it so that a form will only display if another form validates that info is found.

For example:

Form A:

Field 1
Field 2

Form B:

Form B only displays if fields 1 &/or 2 aren't validated in Form A.

What if I want Form B to show only if Form A-Fields 1 & 2 are both validated, and so on...?

Can someone give me a coding template for each?