title: How do I add thousand separators with reg ex?
body: <p>I'm using this free <a href="http://www.radsoftware.com.au/regexdesigner/" rel="nofollow noreferrer">RegExp Designer</a> which does find and replace. How do I search for all numbers and add thousand separators?</p>
  
  <pre><code>Input:      &lt;node num='12345678'&gt;
  Output:     &lt;node num='12,345,678'&gt;
  </code></pre>