title: How can I prevent a screen reader/narrator from reading controls that are hidden in WPF?
body: <p>I have a WPF application, which needs to support accessibility. I have a TextBlock that under certain conditions has its Visibility set to Collapsed.</p>
  
  <p>The Windows 7 narrator and also <a href="http://www.nvda-project.org/">NVDA</a> screen reader both announce the TextBlock even so the Visibility is set to Collapsed.</p>
  
  <p>What do I need to do to prevent it from being read?</p>