<?php

class Qs_Form_Element_Ssn extends Zend_Form_Element_Text
{
    public $placeholder = 'xxx-xx-xxxx';
    public $maxlength = 11;

    public function init()
    {
        parent::init();
        $this->addValidator('Regex', true, [
            'pattern'  => '/^\d{3}-\d{2}-\d{4}$/',
            'messages' => 'Number is in wrong format, use ' . $this->placeholder,
        ]);
    }
}