JQuery change class by given id's
<p>I have a number of tables, for example:</p>

<pre><code>&lt;table class="onion" id="12"&gt;
</code></pre>

<p>When a div named "Mark_Pre_Val" gets clicked i want tables with the id's 4, 6, 12 &amp; 21
to change their class to "onionClick", and if one of them is already "onionClick" then don't
change the class.</p>

<p>Here is the click event:</p>

<pre><code>    $(".Mark_Pre_Val").click(function(){       });
</code></pre>

<p>Can someone point me to the right direction how to approach this?</p>
