title: WPF: copying of XmlElement
body: <p>I create a window in WPF.  The constructor takes a "ref XmlElement settings" which is used to display information in that window.</p>
  
  <p>In the constructor, I clone those settings:</p>
  
  <pre><code>_ClonedSettings = (XmlElement)settings.Clone();
  </code></pre>
  
  <p>and I keep a pointer to the original settings:</p>
  
  <p>_OriginalSettings = settings;</p>
  
  <p>The UI modifies <code>_ClonedSettings</code>. Then if user hits OK button, I want to overwrite the original settings with the <code>_ClonedSettings</code>, so the window creator gets the right values. </p>
  
  <p>How do I do this final copying operation?</p>