Inheritance: extends yii\base\Model
 public function actionMoveSurplus($id)
 {
     try {
         $moveSurplusForm = new MoveSurplusForm($id);
     } catch (InvalidParamException $e) {
         throw new BadRequestHttpException($e->getMessage());
     }
     if ($moveSurplusForm->load(Yii::$app->request->post()) && $moveSurplusForm->move()) {
         Yii::$app->session->setFlash('success', '库存调整完成。');
     } else {
         Yii::$app->session->setFlash('danger', '库存调整失败。');
     }
     return $this->redirect(['surplus', 'id' => $id]);
 }