$re = '/\W\n?(((1|2)[0-9]|3[0-1]|0?[1-9])\/(0?[1-9]|1[0-2])\/((19|20)?[0-9]{2})|((1|2)[0-9]|3[0-1]|0?[1-9])\-(0?[1-9]|1[0-2])\-((19|20)?[0-9]{2})|((19|20)?[0-9]{2})\/((1|2)[0-9]|3[0-1]|0?[1-9])\/(0?[1-9]|1[0-2])|((19|20)?[0-9]{2})\-((1|2)[0-9]|3[0-1]|0?[1-9])\-(0?[1-9]|1[0-2]))\W\n?/m';
$str = ' 12-01-2019
01/10/2019
1-12-1901
04/04/2019
2000-02-12
2000/10/12
1800-1-9
1976/3/1
32/01/3019
9/1/30
5542-21-54
';
preg_match_all($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