I get an undefine error in iframe
<p>I have an iframe below:</p>

<pre><code>&lt;iframe class='upload_target' name='upload_target' src='#' style='width:0;height:0;border:0px;solid;#fff;'&gt;&lt;/iframe&gt;
</code></pre>

<p>I am trying to stop a command below but I keep getting an undefined error: </p>

<pre><code>$('.upload_target').contentwindow is undefined
</code></pre>

<p>How can I fix this undefined error?</p>

<p>Below is code:</p>

<pre><code>   $(".uploadbutton").click(function() {
          $(".upload_target").contentWindow.stop(); //for anything but IE
          $(".upload_target").contentWindow.document.execCommand("Stop"); // for IE
  return stopImageUpload();
</code></pre>

<p>});</p>
