CascadiaPHP 2024

ReflectionClass::getConstants

(PHP 5, PHP 7, PHP 8)

ReflectionClass::getConstants定数を取得する

説明

public ReflectionClass::getConstants(?int $filter = null): array

アクセス権にかかわらず、クラスで定義されているすべての定数を取得します。

パラメータ

filter

オプションのフィルタで、取得したい定数の型を絞り込みます。 ReflectionClassConstant クラスの定数 で設定し、デフォルトではすべての定数を取得します。

戻り値

定数の配列を返します。 キーは名前を保持し、値は定数の値を保持します。

変更履歴

バージョン 説明
8.0.0 filter が追加されました。

参考

add a note

User Contributed Notes 6 notes

up
45
davide dot renzi at gmail dot com
10 years ago
If you want to return the constants defined inside a class then you can also define an internal method as follows:

<?php
class myClass {
const
NONE = 0;
const
REQUEST = 100;
const
AUTH = 101;

// others...

static function getConstants() {
$oClass = new ReflectionClass(__CLASS__);
return
$oClass->getConstants();
}
}
?>
up
17
Sandor Toth
7 years ago
You can pass $this as class for the ReflectionClass. __CLASS__ won't help if you extend the original class, because it is a magic constant based on the file itself.

<?php

class Example {
const
TYPE_A = 1;
const
TYPE_B = 'hello';

public function
getConstants()
{
$reflectionClass = new ReflectionClass($this);
return
$reflectionClass->getConstants();
}
}

$example = new Example();
var_dump($example->getConstants());

// Result:
array ( size = 2)
'TYPE_A' => int 1
'TYPE_B' => (string) 'hello'
up
13
Panni
5 years ago
If you want to define a static getConstants() function which works with inheritance you can do the following:

<?php

abstract class AbstractClass
{
const
TEST = "test";

public static function
getConstants()
{
// "static::class" here does the magic
$reflectionClass = new ReflectionClass(static::class);
return
$reflectionClass->getConstants();
}
}

class
ChildClass extends AbstractClass
{
const
TYPE_A = 1;
const
TYPE_B = 'hello';
}

$example = new ChildClass();
var_dump($example->getConstants());

// Result:
array(3) {
'TYPE_A' => int(1)
'TYPE_B' => string(5) "hello"
'TEST'
=> string(4) "test"
}

?>
up
1
shgninc at gmail dot com
10 years ago
I use a functions to do somthing base on the class constant name as below. This example maybe helpful for everybody.
<?php
public function renderData($question_type = NULL, $data = array()) {
$types = array();
$qt = new ReflectionClass(questionType);
$types = $qt->getConstants();
if (
$type = array_search($question_type, $types)){
//.....Do somthing
}
}
?>
up
4
djhob1972 at yahoo dot com dot au
14 years ago
I was trying to determine how to get a var_dump of constants that are within an interface. Thats right, not using any classes but the interface itself.

Along my travels I found it quite interesting that the ReflectionClass along with a direct call to the interface will also dump its constants. Perfect!!!!

This was using PHP 5.3.1 and my example as below:-

1st File:

constants.php

<?php
<?php>

interface
MyConstants
{
// --------------------------
// Programmatic Level
// --------------------------
const DEBUG_MODE_ACTIVE = FALSE;
const
PHP_VERSION_REQUIREMENT = "5.1.2";
}
?>

=======
Second file:
=======

test.php

<?php>
include_once ("constants.php");

$oClass = new ReflectionClass ('MyConstants');
$array = $oClass->getConstants ();
var_dump ($array);
unset ($oClass);
?>

what you would get from the command line:-

?:\???\htdocs\????>php test.php
array(2) {
["DEBUG_MODE_ACTIVE"]=> bool(false)
["PHP_VERSION_REQUIREMENT"]=> string(5) "5.1.2"

But as you can see this can work quite well to your advantage in many ways so I truely hope this helps someone else with a similar headache in the future to come!

Enjoy!
up
0
dmitrochenkooleg at gmail dot com
5 years ago
Get the latest constants declared.

abstract class AbstractEnum
{
/**
* Возвращает все константы класса || Return all constants
*
* @return array
*/
static function getConstants()
{
$rc = new \ReflectionClass(get_called_class());

return $rc->getConstants();
}

/**
* Возвращает массив констант определенные в вызываемом классе || Return last constants
*
* @return array
*/
static function lastConstants()
{
$parentConstants = static::getParentConstants();

$allConstants = static::getConstants();

return array_diff($allConstants, $parentConstants);
}

/**
* Возвращает все константы родительских классов || Return parent constants
*
* @return array
*/
static function getParentConstants()
{
$rc = new \ReflectionClass(get_parent_class(static::class));
$consts = $rc->getConstants();

return $consts;
}
}

======
class Roles extends AbstractEnum
{
const ROOT = 'root';
const ADMIN = 'admin';
const USER = 'user';
}

// Output:
All: root, admin, user
Last: root, admin, user

class NewRoles extends Roles
{
const CLIENT = 'client';
const MODERATOR = 'moderator';
const SUPERMODERATOR = 'super'.self::USER;
}

// Output:
All: client, moderator, superuser, root, admin, user
Last: client, moderator, superuser

class AdditionalRoles extends Roles
{
const VIEWER = 'viewer';
const CHECKER = 'checker';
const ROOT = 'rooter';
}

All: viewer, checker, rooter, client, moderator, superuser, admin, user
Last: viewer, checker, rooter
To Top