$re = '/^https:\/\/example\.com$/m';
$str = '<p>https://google.com</p>
<p>https://clankapp.com</p>
<p>https://yoyo.com</p>
<p>https://example.com</p>
https://example.com
<p>https://javascript.net/pizza</p>
';
preg_match_all($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