GUMP::validate_min_age PHP Method

    protected function validate_min_age($field, $input, $param = null)
    {
        if (!isset($input[$field]) || empty($input[$field])) {
            return;
        }
        $cdate1 = new DateTime(date('Y-m-d', strtotime($input[$field])));
        $today = new DateTime(date('d-m-Y'));
        $interval = $cdate1->diff($today);
        $age = $interval->y;
        if ($age <= $param) {
            return array('field' => $field, 'value' => $input[$field], 'rule' => __FUNCTION__, 'param' => $param);
        }
    }