title: Check to see if an event handler is attached to and event
body: <p>Add handler</p>
  
  <pre><code>if(!ClickHandled)
      this.Click += (s, e) =&gt;{ }
  </code></pre>
  
  <p>Remove handler:</p>
  
  <pre><code>if(ClickHandled)
      this.Click -= (s, e) =&gt;{ }
  </code></pre>
  
  <p>Is there a way to know if there is already an event handler attached to the control (and possibly get the list of them for example get the list of event handlers for click event)? </p>