javascript - Grab referrer to parent in iFrame (different domain) form hidden field -

i loading form in iframe using javascript , adding referrer url pass parameter iframe (step 1) populating hidden field on form (step 2).

step 1 works fine , yields similar this:

http://www.parentdomain.com/parentpage/?refurl=http://www.somereferringurl.com/somerefpage/

step 2 (where getting stuck)

function gup( grabref )  {    grabref = grabref.replace(/[\[]/,"\\\[").replace(/[\]]/,"\\\]");    var regexs = "[\\?&]"+grabref+"=([^&#]*)";    var regex = new regexp( regexs );    var results = regex.exec( window.location.href );    if( results == null )      return "";    else      return results[1];  }  var referrer = gup( 'refurl' );  function start() {  var ref = document.getelementbyid('my-formfield-id');{  ref.value = referrer;  }  onload = start;         }

this (still) seems yielding parent referrer (http://www.parentdomain.com/parentpage/), , (in fact) seems appending url string closing tag. form , parent reisde in different sub-domains. guessing culprit may lye here: ref.value = referrer;

any ideas?

i unable work resorted grabbing iframe parent referrer , changing parent page (and embedding same form in iframe) capture different campaign referr urls needed. can still grab them in 1 location using same form, have been nice have 1 parent (landing page) , pass along referrer parent.

this code that:

 <script type="text/javascript">     function getparameterbyname(name) {     name = name.replace(/[\[]/, "\\[").replace(/[\]]/, "\\]");     var regex = new regexp("[\\?&]" + name + "=([^&#]*)"),         results = regex.exec(location.search);     return results === null ? "" : decodeuricomponent(results[1].replace(/\+/g, " "));     }     var refval = getparameterbyname('refurl');     //document.write(refval);      function setvalue()     {     document.getelementbyid('my_hidden_formfield_id').value = refval;     //alert(document.getelementbyid('my_hidden_formfield_id').value);  } </script> 

thanks looking.