form validation on form with dynamic fields

[eluser]Brad K Morse[/eluser]
I am using javascript to add extra fields, based on how many the user adds.

I want to retain the data if the form validation does not return true, using set_value()

Since the fields will be dynamically generated by the user, is it possible to still use the form_validation w/ set_value() to accomplish this or I'll need to use javascript to restrict the user from submitting the form until all requirements have been met?

I think validating with javascript over form_validation will be the answer, but I wanted to make sure before proceeding, thank you.