title: How can I check if an event was executed?
body: <p>I am trying to understand how to know that an event was triggered in yii2, and if it got executed correctly.
  So I created an event trigger in <code>yii\base\Controller</code> named <code>EVENT_CONTROLLER_INDEX</code> like this:</p>
  
  <pre><code>const EVENT_CONTROLLER_INDEX='entry-index';
  
  public function render($view, $params = [])
  {
      if($view=='index') {
          $this-&gt;trigger(self::EVENT_CONTROLLER_INDEX);
      }
      $content = $this-&gt;getView()-&gt;render($view, $params, $this);
      return $this-&gt;renderContent($content);
  }
  </code></pre>
  
  <p>Now I want to know where and how can I check it if this event happened?</p>