PatientSearch::getHospitalNumber PHP Method

    public function getHospitalNumber($term)
    {
        $result = null;
        if (preg_match(self::HOSPITAL_NUMBER_REGEX, $term, $matches) || preg_match(Yii::app()->params['hos_num_regex'], $term, $matches)) {
            $hosnum = isset($matches[2]) ? $matches[2] : $matches[1];
            $result = sprintf(Yii::app()->params['pad_hos_num'], $hosnum);
        }
        return $result;
    }

 /**
  * Carry out a search on the waiting list.
  */
 public function actionSearch()
 {
     Audit::add('waiting list', 'search');
     if (empty($_POST)) {
         $operations = array();
     } else {
         $subspecialty_id = !empty($_POST['subspecialty-id']) ? $_POST['subspecialty-id'] : null;
         $firm_id = !empty($_POST['firm-id']) ? $_POST['firm-id'] : null;
         $status = !empty($_POST['status']) ? $_POST['status'] : null;
         $patient_search = new PatientSearch();
         $hos_num = $patient_search->getHospitalNumber($_POST['hos_num']);
         $site_id = !empty($_POST['site_id']) ? $_POST['site_id'] : false;
         YiiSession::set('waitinglist_searchoptions', array('subspecialty-id' => $subspecialty_id, 'firm-id' => $firm_id, 'status' => $status, 'hos_num' => $hos_num, 'site_id' => $site_id));
         $operations = $this->getWaitingList($firm_id, $subspecialty_id, $status, $hos_num, $site_id);
     }
     $this->renderPartial('_list', array('operations' => $operations, 'assetPath' => $this->assetPath), false, true);
 }