function actionUpdate_bind()
 {
     if (!isset(Yii::app()->session['class'])) {
         $this->redirect(array('index'));
     }
     $class = Yii::app()->session['class'];
     if (isset($_REQUEST['bind_class'])) {
         $oldclass = Class_Prog::findByPk($_REQUEST['bind_class']);
         if ($oldclass != null) {
             $class->id_class = $oldclass->id_class;
             $class->isNewRecord = false;
             Yii::app()->session['class'] = $class;
         }
     }
     if ($class->isNewRecord) {
         $this->render('upate/bind');
     } else {
         $this->redirect(array('update_class'));
     }
 }