$re = '/<a.*?example.*?\/a>/s';
$str = '<a href="http://example.com">
1rer</a>vcbn
<a
href="http://example.com/fdfdsfds">fdsfsdfsd</a>cvbn
<a class="fff" href="http://example.com/dsdaas">3e2fdf fdsfds</a>';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php