Date Format Validation in PHP

How can you validate date format in php using Regex and without Regex using simple php date function. If you are working on any application where right data format is mandatory then you must have to apply right data format validation on server side so that you can easily calculate taken duration for any task.

Going to validate this format YYYY-MM-DD

Date Format Validation using Regex

function validateDate($data) {
if (preg_match("/^[0-9]{4}-(0[1-9]|1[0-2])-(0[1-9]|[1-2][0-9]|3[0-1])$/",$date))
    {
        return true;
    }else{
        return false;
    }
}

var_dump(validateDate("2017-02-27")) // true
var_dump(validateDate("27-02-2017")) // false
var_dump(validateDate("2017-14-27")) // false

Date Format Validation using PHP Date object

function validateDate($date)
{
    $dt = DateTime::createFromFormat('Y-m-d', $date);
    return $dt && $dt->format('Y-m-d') === $date;
}
var_dump(validateDate("2017-02-27")) // true
var_dump(validateDate("27-02-2017")) // false
var_dump(validateDate("2017-14-27")) // false