final protected function crawl(string $url, array $params = []): ?Crawler
    {
        if ($content = $this->connection->getPageBody($url, $params)) {
            return new Crawler($content);
        }

        return null;
    }
final protected function crawl(string $url, array $params = []): ?Crawler
    {
        if ($content = $this->connection->getPageBody($url, $params)) {
            return new Crawler($content);
        }

        return null;
    }
final protected function crawl ( string $ url , array $ params = [ ] ) : ? Crawler { if ( $ content = $ this -> connection -> getPageBody ( $ url , $ params ) ) { return new Crawler ( $ content ) ; } return null ; }
Crawles a url.

@param string $url
@param array  $params

@return Crawler|null
Crawles a url .