The WeakReference class

Intro

Weak references allow the programmer to retain a reference to an object without preventing the object from being destroyed. They are useful for implementing cache-like structures. If the original object has been destroyed, null will be returned when calling the WeakReference::get method. The original object will be destroyed when the refcount for it drops to zero; creating weak references does not increase the refcount of the object being referenced.

WeakReferences cannot be serialized.

Class synopsis

WeakReference Examples

Basic WeakReference Usage

<?php

$obj = new stdClass();
$weakref = WeakReference::create($obj);

var_dump($weakref->get());

unset($obj);

var_dump($weakref->get());

?>

The above example will output something similar to:

object(stdClass)#1 (0) {
}
NULL

Changelog

Construct Create Get