$re = '/^([0-2][0-9]|3[0-1])(\/|-)(0[1-9]|1[0-2])\2(\d{4})(\s)([0-1][0-9]|2[0-3])(:)([0-5][0-9])$/';
$str = '28/05/2017 00:06';
preg_match($re, $str, $matches, PREG_OFFSET_CAPTURE, 0);
// Print the entire match result
var_dump($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