title: Get the width of a div when width set by css class
body: <p>This JS script gives me an alertbox saying;</p>
  
  <pre><code>jQuery.UI.version = 1.0.2  ---   Box Width: undefined
  </code></pre>
  
  <p>How can I select the <code>#resizable</code>?</p>
  
  <pre><code> &lt;head&gt;
      &lt;title&gt;&lt;/title&gt;
      &lt;link href="StyleSheet.css" rel="stylesheet" type="text/css" /&gt;
      &lt;script src="jquery-1.9.1.min.js" type="text/javascript"&gt;&lt;/script&gt;
      &lt;script src="jquery-ui-1.10.2.custom.min.js" type="text/javascript"&gt;&lt;/script&gt;
         &lt;style&gt;
    #resizable { width: 200px; height: 150px; padding: 5px; border: 1px solid red;}
  
    &lt;/style&gt;
  
        &lt;script&gt;
          $(function () {
              var boxWidth = $('#resizable').attr('width');
              alert("jQuery.UI.version = " + jQuery.ui.version + "  ---   Box Width: " + boxWidth);           
          });
    &lt;/script&gt;
  
  
  &lt;/head&gt;
  &lt;body&gt;
      &lt;div id="resizable" class="&gt;
          &lt;div id="title"&gt;
              &lt;h2&gt;
              The expanding box
              &lt;/h2&gt;
          &lt;/div&gt;    
      &lt;/div&gt;
  &lt;/body&gt;
  </code></pre>