jQuery for...in toUpperCase is not a function
<p>With typical input as below...</p>

<pre><code>&lt;input type="checkbox" class="actEmail" data-value="1"/&gt;Department one&lt;/li&gt;
</code></pre>

<p>in my function...</p>

<pre><code>var chksDept = $('input[type=checkbox].actEmail:checked');
var depts = Array();

chksDept.each(function() { 
    depts.push($(this).data('value').toUpperCase());  
});
</code></pre>

<p>Why I got the error : </p>

<blockquote>
  <p><code>$(...).data(...).toUpperCase()</code> is not a function?</p>
</blockquote>

<p>What I need is to grab all data value in uppercase. </p>
