I have been working on my date regular expression all day... I want a date format to be YYYY-MM-DD.

$date_regex ='^(19|20)\d\d[- /.](0[1-9]|1[012])[- /.](0[1-9]|[12][0-9]|3[01])$';

if (preg_match($date_regex, $dateString)) {
        echo "good format";
    }

bana hata veren tutar

preg_match () [function.preg-match]: Hayır biten ayracı '^' hat 19 üzerinde test.php bulundu

Kimse yardımcı? Thanks a lot!