php - Parsing Javascript on server -

i trying create a basic web crawler looks links adverts.

i have managed find script uses curl contents of target webpage

<?php  $ch = curl_init("http://www.nbcnews.com"); $fp = fopen("source_code.txt", "w");  curl_setopt($ch, curlopt_file, $fp); curl_setopt($ch, curlopt_header, 0);  curl_exec($ch); curl_close($ch); fclose($fp); ?> 

i found 1 uses dom

<?php $html = file_get_contents('http://www.nbcnews.com');  $dom = new domdocument(); @$dom->loadhtml($html);  // grab on page $xpath = new domxpath($dom); $hrefs = $xpath->evaluate("/html/body//i");  ($i = 0; $i < $hrefs->length; $i++) {    $href = $hrefs->item($i);    $url = $href->getattribute('href');    echo $url.'<br />'; } ?> 

these great , feel i'm heading in right direction except quite few adverts displayed using js , it's client side, isn't processed , see js code , not ads.

basically, there way of getting js execute before start trying extract links?

thanks