WeakRef (class)
Introduction
(PECL weakref >= 0.1.0)
The WeakRef class provides a gateway to objects without preventing the garbage collector from freeing those objects. It also provides a way to turn a weak reference into a strong one.
Class synopsis
WeakRef {
/* Methods */
public Weakref::__construct ( object $object )
public bool Weakref::acquire ( void )public object Weakref::get ( void )public bool Weakref::release ( void )public bool Weakref::valid ( void )}
Examples
Example #1 WeakRef usage example
<?php
class?MyClass?{
????public?function?__destruct()?{
????????echo?"Destroying?object!\n";
????}
}
$o1?=?new?MyClass;
$r1?=?new?WeakRef($o1);
if?($r1->valid())?{
????echo?"Object?still?exists!\n";
????var_dump($r1->get());
}?else?{
????echo?"Object?is?dead!\n";
}
unset($o1);
if?($r1->valid())?{
????echo?"Object?still?exists!\n";
????var_dump($r1->get());
}?else?{
????echo?"Object?is?dead!\n";
}
?>The above example will output:
Object still exists!
object(MyClass)#1 (0) {
}
Destroying object!
Object is dead!Table of Contents
- Weakref::acquire — Acquires a strong reference on that object
- Weakref::__construct — Constructs a new weak reference
- Weakref::get — Returns the object pointed to by the weak reference
- Weakref::release — Releases a previously acquired reference
- Weakref::valid — Checks whether the object referenced still exists
Weakref::acquire →
? 1997–2017 The PHP Documentation GroupLicensed under the Creative Commons Attribution License v3.0 or later.
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