WeakMap (class)
Introduction
(PECL weakref >= 0.2.0)
Class synopsis
WeakMap implements Countable , ArrayAccess , Iterator {
/* Methods */
public __construct ( void )public int count ( void )public mixed current ( void )public object key ( void )public void next ( void )public bool offsetExists ( object $object )public mixed offsetGet ( object $object )public void offsetSet ( object $object , mixed $value )public void offsetUnset ( object $object )public void rewind ( void )public bool valid ( void )}
Examples
Example #1 Weakmap usage example
<?php
$wm?=?new?WeakMap();
$o?=?new?StdClass;
class?A?{
????public?function?__destruct()?{
????????echo?"Dead!\n";
????}
}
$wm[$o]?=?new?A;
var_dump(count($wm));
echo?"Unsetting..\n";
unset($o);
echo?"Done\n";
var_dump(count($wm));The above example will output:
int(1)
Unsetting..
Dead!
Done
int(0)Table of Contents
- WeakMap::__construct — Constructs a new map
- WeakMap::count — Counts the number of live entries in the map
- WeakMap::current — Returns the current value under iteration
- WeakMap::key — Returns the current key under iteration.
- WeakMap::next — Advances to the next map element
- WeakMap::offsetExists — Checks whether a certain object is in the map
- WeakMap::offsetGet — Returns the value pointed to by a certain object
- WeakMap::offsetSet — Updates the map with a new key-value pair
- WeakMap::offsetUnset — Removes an entry from the map
- WeakMap::rewind — Rewinds the iterator to the beginning of the map
- WeakMap::valid — Returns whether the iterator is still on a valid map element
← Weakref::valid
WeakMap::__construct →
? 1997–2017 The PHP Documentation GroupLicensed under the Creative Commons Attribution License v3.0 or later.
本文档系腾讯云开发者社区成员共同维护，如有问题请联系 cloudcommunity@tencent.com
