Yii中事件触发机制

public function init()
{
parent::init(); // TODO: Change the autogenerated stub
Yii::$app->on('yii2event',function($event){
$args=$event->sender;
echo $args['name'];
echo "<br/>";
Yii::$app->off('yii2event');
});
}
public function actionYii2event(){
Yii::$app->trigger('yii2event',new Event(['sender'=>['age'=>18,'sex'=>'mail','name'=>'Hello world']]));
}