title: Can't use CefSharp' IJsDialogHandler to catch the JavaScript alert event
body: <p>I would like to catch the javascript alert event by IJsDialogHandler of CefSharp. But, I have four events of IJsDialogHandler listed as below:</p>
  
  <pre><code>    public void OnDialogClosed(IWebBrowser browserControl, IBrowser browser)
      {
      }
  
      public bool OnJSBeforeUnload(IWebBrowser browserControl, IBrowser browser, string message, bool isReload, IJsDialogCallback callback)
      {
          return true;
      }
  
      public bool OnJSDialog(IWebBrowser browserControl, IBrowser browser, string originUrl, string acceptLang, CefJsDialogType dialogType, string messageText, string defaultPromptText, IJsDialogCallback callback, ref bool suppressMessage)
      {
          if (Host != null)
          {
              Host.HandleDialog(messageText);
          }
  
          return true;
      }
  
      public void OnResetDialogState(IWebBrowser browserControl, IBrowser browser)
      {
      }
  </code></pre>
  
  <p>However, none of them can catch the Javascript alert event from the website.
  For example: please visit this website and choose the follow conditions as below, you will see the javascript alert event.</p>
  
  <p>Website is        <a href="http://www.travellers-autobarn.com.au/" rel="nofollow">http://www.travellers-autobarn.com.au/</a></p>
  
  <p>Conditions are: (Pick up: Brisbane        Pick up date: 26/01/2016
                   Returning: Brisbane      Returning date: 04/02/2016)</p>
  
  <p>Really appreciate if someone who can figure it out, I have tried several ways to catch this Javascript alert event, but still got nothing.</p>