login login login

public $modelClass = 'app\models\LoginForm';

     public function actionLogin() {

         $username = Yii::$app->request->post('username');
         $password = Yii::$app->request->post('password');
         $loginForm = new \app\models\LoginForm();
         $loginForm->username = $username;
         $loginForm->password = $password;
         $success = $loginForm->login();
         echo $success == true ? 'OK' : 'NOK';
     }