How to return 'null' instead of 'undefined' from select element
<p>How can I return null instead of a 'undefined' from a select element.</p>

<p>Basically I have 4 selects at the moment, but only the first one is populated with data at this point, but I want to grab the value from all of them when working with them.</p>

<pre><code>&lt;select class="changeValue" id="drpOne"&gt;&lt;/select&gt;
&lt;option id=1&gt;1&lt;/option&gt;
&lt;option id=2&gt;2&lt;/option&gt;
&lt;option id=3&gt;3&lt;/option&gt;

&lt;select class="changeValue" id="drpTwo"&gt;&lt;/select&gt;
</code></pre>

<p>JQuery:</p>

<pre><code>$('.changeValue').change(function() {
    var data = {};
    data["Id1"] = $('#drpOne:selected').attr("id");
    data["Id2"] = $('#drpTwo:selected').attr("id");
</code></pre>

<p>In this case, drpTwo will return 'undefined'. Is there anyway to get a null instead?</p>
