<?php
class Selectordom {
    public function get($url) {    
        $dom = new DOMDocument();
        $ch = curl_init();
        curl_setopt($ch, CURLOPT_URL, $url);
        curl_setopt($ch, CURLOPT_HEADER, false);  
        curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 2);
        curl_setopt($ch, CURLOPT_SSLVERSION, 0);
        curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 0);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
        //curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
        curl_setopt($ch, CURLOPT_USERAGENT, $_SERVER['HTTP_USER_AGENT']);

        $buffer = curl_exec($ch);
        curl_close($ch);

        //$buffer = mb_convert_encoding($buffer, 'HTML-ENTITIES', 'UTF-8');
        @$dom->loadHTML($buffer);
        $this->xpath = new DOMXpath($dom);
    }
    public function select($selector, $as_array = true) {
        $elements = $this->xpath->evaluate($this->selector_to_xpath($selector));
        return $as_array ? $this->elements_to_array($elements) : $elements;
    }
    public function elements_to_array($elements) {
        $array = array();
        for ($i = 0, $length = $elements->length; $i < $length; ++$i)
            if ($elements->item($i)->nodeType == XML_ELEMENT_NODE)
                array_push($array, $this->element_to_array($elements->item($i)));
            return $array;
    }
    public function innerXML($node) {
        $doc  = $node->ownerDocument;

        $frag = @$doc->createDocumentFragment();

        foreach ($node->childNodes as $child) {
            @$frag->appendChild($child->cloneNode(TRUE));
        }

        return (string) $doc->saveXML($frag);
    }
    public function element_to_array($element) {
        $array = array(
            'name' => $element->nodeName,
            'attributes' => array(),
            'text' => $element->textContent,
            'html' => $this->innerXML($element),
            'children' => $this->elements_to_array($element->childNodes)
        );
        if ($element->attributes->length)
            foreach($element->attributes as $key => $attr)
                $array['attributes'][$key] = $attr->value;
            return $array;
    }
    public function selector_to_xpath($selector) {
        $selector = preg_replace('/\s*>\s*/', '>', $selector);
        $selector = preg_replace('/\s*~\s*/', '~', $selector);
        $selector = preg_replace('/\s*\+\s*/', '+', $selector);
        $selector = preg_replace('/\s*,\s*/', ',', $selector);
        $selectors = preg_split('/\s+(?![^\[]+\])/', $selector);

        foreach ($selectors as &$selector) {
            // ,
            $selector = preg_replace('/,/', '|descendant-or-self::', $selector);
            // input:checked, :disabled, etc.
            $selector = preg_replace('/(.+)?:(checked|disabled|required|autofocus)/', '\1[@\2="\2"]', $selector);
            // input:autocomplete, :autocomplete
            $selector = preg_replace('/(.+)?:(autocomplete)/', '\1[@\2="on"]', $selector);
            // input:button, input:submit, etc.
            $selector = preg_replace('/:(text|password|checkbox|radio|button|submit|reset|file|hidden|image|datetime|datetime-local|date|month|time|week|number|range|email|url|search|tel|color)/', 'input[@type="\1"]', $selector);
            // foo[id]
            $selector = preg_replace('/(\w+)\[([_\w-]+[_\w\d-]*)\]/', '\1[@\2]', $selector);
            // [id]
            $selector = preg_replace('/\[([_\w-]+[_\w\d-]*)\]/', '*[@\1]', $selector);
            // foo[id=foo]
            $selector = preg_replace('/\[([_\w-]+[_\w\d-]*)=[\'"]?(.*?)[\'"]?\]/', '[@\1="\2"]', $selector);
            // [id=foo]
            $selector = preg_replace('/^\[/', '*[', $selector);
            // div#foo
            $selector = preg_replace('/([_\w-]+[_\w\d-]*)\#([_\w-]+[_\w\d-]*)/', '\1[@id="\2"]', $selector);
            // #foo
            $selector = preg_replace('/\#([_\w-]+[_\w\d-]*)/', '*[@id="\1"]', $selector);
            // div.foo
            $selector = preg_replace('/([_\w-]+[_\w\d-]*)\.([_\w-]+[_\w\d-]*)/', '\1[contains(concat(" ",@class," ")," \2 ")]', $selector);
            // .foo
            $selector = preg_replace('/\.([_\w-]+[_\w\d-]*)/', '*[contains(concat(" ",@class," ")," \1 ")]', $selector);
            // div:first-child
            $selector = preg_replace('/([_\w-]+[_\w\d-]*):first-child/', '*/\1[position()=1]', $selector);
            // div:last-child
            $selector = preg_replace('/([_\w-]+[_\w\d-]*):last-child/', '*/\1[position()=last()]', $selector);
            // :first-child
            $selector = str_replace(':first-child', '*/*[position()=1]', $selector);
            // :last-child
            $selector = str_replace(':last-child', '*/*[position()=last()]', $selector);
            // :nth-last-child
            $selector = preg_replace('/:nth-last-child\((\d+)\)/', '[position()=(last() - (\1 - 1))]', $selector);
            // div:nth-child
            $selector = preg_replace('/([_\w-]+[_\w\d-]*):nth-child\((\d+)\)/', '*/*[position()=\2 and self::\1]', $selector);
            // :nth-child
            $selector = preg_replace('/:nth-child\((\d+)\)/', '*/*[position()=\1]', $selector);
            // :contains(Foo)
            $selector = preg_replace('/([_\w-]+[_\w\d-]*):contains\((.*?)\)/', '\1[contains(string(.),"\2")]', $selector);
            // >
            $selector = preg_replace('/>/', '/', $selector);
            // ~
            $selector = preg_replace('/~/', '/following-sibling::', $selector);
            // +
            $selector = preg_replace('/\+([_\w-]+[_\w\d-]*)/', '/following-sibling::\1[position()=1]', $selector);
            $selector = str_replace(']*', ']', $selector);
            $selector = str_replace(']/*', ']', $selector);
        }

        // ' '
        $selector = implode('/descendant::', $selectors);
        $selector = 'descendant-or-self::' . $selector;
        // :scope
        $selector = preg_replace('/(((\|)?descendant-or-self::):scope)/', '.\3', $selector);
        // $element
        $sub_selectors = explode(',', $selector);

        foreach ($sub_selectors as $key => $sub_selector) {
            $parts = explode('$', $sub_selector);
            $sub_selector = array_shift($parts);

            if (count($parts) && preg_match_all('/((?:[^\/]*\/?\/?)|$)/', $parts[0], $matches)) {
                $results = $matches[0];
                $results[] = str_repeat('/..', count($results) - 2);
                $sub_selector .= implode('', $results);
            }

            $sub_selectors[$key] = $sub_selector;
        }

        $selector = implode(',', $sub_selectors);

        return $selector;
    }
}

<?php
header('Content-type: application/json');
include 'Selectordom.php';

$Selector = new Selectordom();
$Selector->get('https://www.r10.net/php/2985702-preg_match_all-yardim.html');

exit(json_encode($Selector->select('.userSignature')));