Question

$twoform = new TwoForm;

$this->embedForm('twoform', $twoform);

 if($value == false) {
  // unembedForm twoform  HOW?
}

how can i make if $value == false then form twoform is not submit and not add to database? unset fields not working, because form is sending, but it has a NULL value.

Answer 1

You can do this to unset form

unset($this->widgetSchema['twoForm']);
unset($this->validatorSchema['twoForm']);
unset($this->formFieldSchema['twoForm']);

But this won’t avoid posting the form in cas it was previously visible. You can replace validator to ignore posted values.
$this->setValidator('twoForm', new sfValidatorPass());

If the exemple given is complete, the better is imho not to embed the form if $value == false

The database insertion depends on how your data is saved into it (sfDoctrineForm ?)