Online PHP editor | output for DZQj4

<?php function getValue($html, $tag, $attr) { $dom = new DOMDocument; $dom->loadHTML($html); $xpath = new DOMXPath($dom); $result = []; foreach ($xpath->query("//{$tag}[@{$attr}]") as $node) { $result[] = $node->getAttribute($attr); } return implode(',', $result); } $html = '<a data-id="777777"></a><a data-id="888888"></a><a data-id="99999"></a>'; $tag = 'a'; $attr = 'data-id'; echo getValue($html, $tag, $attr); echo "\n---\n"; $html = '<a data-A="AAAAAA"></a><a data-A="BBBBBB"></a><a data-A="CCCCCC"></a>'; $tag = 'a'; $attr = 'data-a'; echo getValue($html, $tag, $attr);