Zend Form MutliCheckbox Validate Number of Checked Items

Question

I have a Zend Form with a MutliCheckbox element.

I would like to validate the number of checked items, i.e. verify that exactly 3 items are checked.

Can I do it with any current validates or do I have to write my own?

Thanks.

Answer 1

You will have to write your own, but that's quite simple. There is a second optional argument on the isValid() method that gives you access to all the form values, and enables this way to validate against multiple inputs.

class MyValidator extends Zend_Validate_Abstract {
    public function isValid($value, $formData = null){
        //you can access to all the form values in the $formData, and check/count
        //the values of your multicheckbox
        //this is the super-quick way, but you could also add error messages
        return $isValid;
    }
}

and then add it to your element

$myElement->addValidator( new MyValidator());