title: JQuery - fadeIn using variable instead of id?
body: <p>This code works:</p>
  
  <pre><code>$(contentDiv).fadeIn("slow");
  </code></pre>
  
  <p>This does not:</p>
  
  <pre><code>var elementName = 'contentDiv';
  $(elementName).fadeIn("slow");
  </code></pre>
  
  <p>No fade effect appears.</p>
  
  <p>I'm about to feel like an idiot with this solution I know but I can't work it out.</p>