Enable/disable button depending on whether an input in a text box is in a select box
<p>I have nearly finished writing this code: <a href="http://jsfiddle.net/2Jkk9/11/" rel="nofollow">http://jsfiddle.net/2Jkk9/11/</a></p>

<p>but I can't figure out how to search the select box for the value in my text box and enable/disabled the button accordingly.</p>

<p>That's probably enough explanation.. the code explains all...</p>

<p>Thank you :).</p>

<p><strong>EDIT</strong> Here's my original code from jsfiddle:</p>

<pre><code>&lt;select id="myselect"&gt;
    &lt;option&gt;apple&lt;/option&gt;
    &lt;option&gt;banana&lt;/option&gt;
    &lt;option&gt;pear&lt;/option&gt;
&lt;/select&gt;
&lt;br&gt;&lt;br&gt;
&lt;input id="filter" type="text"/&gt;
</code></pre>

<p>and</p>

<pre><code>$(function() {
    $('#filter').keyup(function() {
         // if select box contains input then
         //   $('#mybtn').attr(disabled, 'disabled');
         //}
         //else {
         //   $('#mybtn').removeAttr('disabled');
         //}
    });
});
</code></pre>
