$re = '/(www.)?ucwebapi(\-uccore\d{0,3}\-?\d{0,3})?\.testme\.net/';
$str = 'ucwebapi.testme.net
ucwebapi-uccore.testme.net
ucwebapi-uccore1-0.testme.net
ucwebapi-uccore999-999.testme.net
';
preg_match_all($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