title: How can I get Iframe event before load?
body: <p>In my site, I use an iframeA in an iframeB, and, when the iframeA changes it's content I have to set the src. I can set it only with the onload event, but this called when the site is loaded. I am looking for some event or trigger, that helps me detect the location/src change before it starts loading. I don't want to wait the whole page load, before the src set. I have no direct access to iframeA (just the script below)</p>
  
  <p>Some code:</p>
  
  <pre><code>var myframe = document.getElementById('frameB').contentWindow.document.getElementById('frameA');
  myframe.onload=function (funcname) {...};
  </code></pre>