Adding VistorID to a URL parameter


I would like to add the Visitor ID of the site visitor on the page as a outbound URL parameter on same page. My code looks like this:

<script type="text/javascript">
function delayer(){
    window.location = ""something"&source="MatomoVisitorID"

    <!-- Matomo -->
<script type="text/javascript">
  var _paq = _paq || [];
  /* tracker methods like "setCustomDimension" should be called before "trackPageView" */
  (function() {
    var u="//";
    _paq.push(['setTrackerUrl', u+'piwik.php']);
    _paq.push(['setSiteId', '7']);
    var d=document, g=d.createElement('script'), s=d.getElementsByTagName('script')[0];
    g.type='text/javascript'; g.async=true; g.defer=true; g.src=u+'piwik.js'; s.parentNode.insertBefore(g,s);
  var visitor_id;
_paq.push([ function() { visitor_id = this.getVisitorId(); }]);
<!-- End Matomo Code -->
<body onLoad="setTimeout('delayer()', 1000)">



What do I need to add instead of “MatomoVisitorID” in the URL above to make this work?

Thanks in advance for your help!