What does the ?? operator do?
<blockquote>
  <p><strong>Possible Duplicate:</strong><br>
  <a href="http://stackoverflow.com/questions/827454/what-is-the-operator-for">What is the &ldquo;??&rdquo; operator for?</a>  </p>
</blockquote>



<p>I have recently come across the <code>??</code> operator in C#.  What does this operator do and when would someone use it?</p>

<p>Example:</p>

<pre><code>string name = nameVariable ?? string.Empty;
</code></pre>
