public function getladderqtyAction()
 {
     $request = $this->getRequest()->getParams();
     $ladder_id = isset($request['ladder_id']) ? $request['ladder_id'] : null;
     if ($ladder_id) {
         $qty = new Erp_Model_Warehouse_Ladderqty();
         echo Zend_Json::encode($qty->getData($ladder_id));
     }
     exit;
 }