$re = '/^(?!0\d)\d{1,3}(?:\.\d{3})*,\d{2}$/m';
$str = '1.123,45
1,23
1.234.567,45
0,56
0,00
12
01,56
1,5
01,100.36
1,1236.25';
preg_match_all($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