PHP：创建自定义filter_var（）常量

Question

How would i go about creating custom filters for use in PHP filter_var() .

An example:

Right now i have a function to validate a date:

    private function validateDate($date){
        $d = DateTime::createFromFormat('Y-m-d', $date);
        return $d && $d->format('Y-m-d') == $date;
    }

^{function was copied from this answer or php.net}

I want to be able to call a constant like FILTER_VALIDATE_DATE and have it checked by the above code.

Any help is appreciated.

Answer 1

PHP没有为您注册自定义过滤器的方法，因此您不能简单地传递一个新的常量。最好的办法是使用FILTER_CALLBACK并将回调作为第三个参数传递，就像这样：

$valid = filter_var($date, FILTER_CALLBACK, ['options' => 'validateDate']);

Answer 2

You should use filter callback functions.

$date = "2015-06-30";

echo filter_input( $date, FILTER_CALLBACK, array('options' => 'validateDate') );