Overview
KB
Technical FAQ
PHP Manual
CSS2 Manual
HTML Manual
JS Guide
JS Reference
PhpDock Manual
Nu-Coder Manual
PhpExpress Manual
PHP Joomla
Development
Learn PHP
 
<ReflectionReference::fromArrayElementReflectionAttribute>
^ReflectionReferenceLast updated: Mon, 26 Oct 2026

ReflectionReference::getId

(PHP 7 >= 7.4.0, PHP 8)

ReflectionReference::getId — Get unique ID of a reference

Description

public function ReflectionReference::getId(): string

Returns an ID which is unique for the reference for the lifetime of that reference. This ID can be used to compare references for equality, or to maintain a map of known references.

Parameters

This function has no parameters.

Return Values

Returns a string of unspecified format.

Examples

Example #1 Basic ReflectionReference::getId() usage

<?php
$val1 = 'foo';
$val2 = 'bar';
$arr = [&$val1, &$val2, &$val1];

$rr1 = ReflectionReference::fromArrayElement($arr, 0);
$rr2 = ReflectionReference::fromArrayElement($arr, 1);
$rr3 = ReflectionReference::fromArrayElement($arr, 2);

var_dump($rr1->getId() === $rr2->getId());
var_dump($rr1->getId() === $rr3->getId());
?>

The above example will output:

bool(false)
bool(true)

<ReflectionReference::fromArrayElementReflectionAttribute>
^ReflectionReferenceLast updated: Mon, 26 Oct 2026