PHP Regex to check date is in YYYY-MM-DD format

Question

I\'m trying to check that dates entered by end users are in the YYYY-MM-DD. Regex has never been my strong point, I keep getting a false return value for the preg_match() I

Answer 1

This should tell you if the format is valid and if the input date is valid.

    $datein = '2012-11-0';

    if(preg_match('/^[0-9]{4}-(0[1-9]|1[0-2])-(0[1-9]|[1-2][0-9]|3[0-1])$/', $datein)){
        echo 'good';
    }else{
        echo 'no good';
    }