$re = '/^(?=.{1,23}$)^\w+\s*(-?)(\s*\w+\s*)(\w+)$/m';
$str = 'The cases I need to pass:
Winston1-Salem6
Winston-Salem
Winston Salem
1-two3
word2 with space
Cases I need to fail:
-Newberty-Los-
12345678901234567890123444
';
preg_match_all($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