How to change string to make in integer?

How to translate $ string to integer using filter_var?

$client = new Client(); // Go to the booking.com website $crawler = $client->request('GET', 'http://www.booking.com/country.en-gb.html'); $crawler = $crawler->filter('body#b2countryPage > div#bodyconstraint > div#bodyconstraint-inner > div.lp_flexible_layout_content_wrapper > div#countryTmpl > div.block_third > div.block_header'); foreach ($crawler as $domElement) { //var_dump($domElement->getElementsByTagName('h2')->item(0)->textContent); // var_dump($domElement->getElementsByTagName('span')->item(0)->textContent); $string = $domElement->getElementsByTagName('span')->item(0)->textContent var_dump(filter_var($string, )); $countries = new Countries(); $countries->setCountry($domElement->getElementsByTagName('h2')->item(0)->textContent); $countries->setHotels($domElement->getElementsByTagName('span')->item(0)->textContent); $doctrine = $this->getContainer()->get('doctrine'); $em = $doctrine->getManager(); $em->persist($countries); $em->flush(); } } 

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