cobaController.php

<?php

//class Controller

    public function actionContact()
{
    $model = new DynamicModel([
        'name', 'body'
    ]);
    $model->addRule(['name', 'body'], 'required')
    ->addRule(['name'],'unique');
 
    if ($model->load(Yii::$app->request->post()) && $model->validate()) {
       echo json_encode($model->attributes);
 exit();
        return $this->refresh();
    }
    return $this->render('contact', ['model' => $model]);
}

?>