title: Get a class name by knowing part of it's name when it's not the only class applied to an element
body: <p>I'm looking for a way using jquery/javascript to get a class name when I only know part of it and there are more than one classes applied to that element.</p>
  
  <p>So if I'm looking for a class that I know starts with "charLimit_" I want to know that full class name even when it's not the only class applied to a given element.
  Example HTML would be.</p>
  
  <pre><code>&lt;input class="charLimit_30 lastNameValidation" type="text" /&gt;
  </code></pre>
  
  <p>What I have so far below will put both "charLimit_30" and "lastNameValidation" into an array, but how do I then say I only want "charLimit_30" and then only tell me the value found after the underscore (30).</p>
  
  <pre><code>var classMName = $('[class*=charLimit_]').attr("class").split(' ');
  </code></pre>
  
  <p>Thanks in advance for you help!!!</p>