title: How can I determine if my TextBlock text is being trimmed?
body: <p>The following textblock wraps and trims as expected. The elipsis "..." is displayed when the text is trimmed.</p>
  
  <pre><code>&lt;TextBlock 
      MaxWidth="60" 
      MaxHeight="60" 
      Text="This is some long text which I would like to wrap."
      TextWrapping="Wrap" 
      TextTrimming="CharacterEllipsis" /&gt;
  </code></pre>
  
  <p>I would like to display a tooltip over the text with the full text, but only if the text is trimmed. I'm not sure how to reliably determine if the "..." is being shown or not.</p>
  
  <p>How do I determine if the text is being trimmed or not?</p>