ProductToCategory::rules PHP Méthode

    public function rules()
    {
        // NOTE: you should only define rules for those attributes that
        // will receive user inputs.
        return array(array('product_id, category_id', 'required'), array('product_id, category_id', 'numerical', 'integerOnly' => true), array('product_id, category_id', 'safe', 'on' => 'search'));
    }