<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="content-type" content="text/html; charset=UTF-8"> <title>The WeakMap class</title> </head> <body><div class="manualnavbar" style="text-align: center;"> <div class="prev" style="text-align: left; float: left;"><a href="weakref.valid.html">Weakref::valid</a></div> <div class="next" style="text-align: right; float: right;"><a href="weakmap.construct.html">WeakMap::__construct</a></div> <div class="up"><a href="book.weakref.html">Weakref</a></div> <div class="home"><a href="index.html">PHP Manual</a></div> </div><hr /><div id="class.weakmap" class="reference"> <h1 class="title">The WeakMap class</h1> <div class="partintro"><p class="verinfo">(PECL weakref >= 0.2.0)</p> <div class="section" id="weakmap.intro"> <h2 class="title">Introduction</h2> <p class="para"> </p> </div> <div class="section" id="weakmap.synopsis"> <h2 class="title">Class synopsis</h2> <div class="classsynopsis"> <div class="ooclass"></div> <div class="classsynopsisinfo"> <span class="ooclass"> <strong class="classname">WeakMap</strong> </span> <span class="oointerface">implements <span class="interfacename"><a href="class.countable.html" class="interfacename">Countable</a></span> </span> <span class="oointerface">, <span class="interfacename"><a href="class.arrayaccess.html" class="interfacename">ArrayAccess</a></span> </span> <span class="oointerface">, <span class="interfacename"><a href="class.iterator.html" class="interfacename">Iterator</a></span> </span> {</div> <div class="classsynopsisinfo classsynopsisinfo_comment">/* Methods */</div> <div class="methodsynopsis dc-description"> <span class="modifier">public</span> <span class="methodname"><a href="weakmap.construct.html" class="methodname">__construct</a></span> ( <span class="methodparam">void</span> )</div> <div class="methodsynopsis dc-description"> <span class="modifier">public</span> <span class="type">int</span> <span class="methodname"><a href="weakmap.count.html" class="methodname">count</a></span> ( <span class="methodparam">void</span> )</div> <div class="methodsynopsis dc-description"> <span class="modifier">public</span> <span class="type">mixed</span> <span class="methodname"><a href="weakmap.current.html" class="methodname">current</a></span> ( <span class="methodparam">void</span> )</div> <div class="methodsynopsis dc-description"> <span class="modifier">public</span> <span class="type">object</span> <span class="methodname"><a href="weakmap.key.html" class="methodname">key</a></span> ( <span class="methodparam">void</span> )</div> <div class="methodsynopsis dc-description"> <span class="modifier">public</span> <span class="type">void</span> <span class="methodname"><a href="weakmap.next.html" class="methodname">next</a></span> ( <span class="methodparam">void</span> )</div> <div class="methodsynopsis dc-description"> <span class="modifier">public</span> <span class="type">bool</span> <span class="methodname"><a href="weakmap.offsetexists.html" class="methodname">offsetExists</a></span> ( <span class="methodparam"><span class="type">object</span> <code class="parameter">$object</code></span> )</div> <div class="methodsynopsis dc-description"> <span class="modifier">public</span> <span class="type">mixed</span> <span class="methodname"><a href="weakmap.offsetget.html" class="methodname">offsetGet</a></span> ( <span class="methodparam"><span class="type">object</span> <code class="parameter">$object</code></span> )</div> <div class="methodsynopsis dc-description"> <span class="modifier">public</span> <span class="type">void</span> <span class="methodname"><a href="weakmap.offsetset.html" class="methodname">offsetSet</a></span> ( <span class="methodparam"><span class="type">object</span> <code class="parameter">$object</code></span> , <span class="methodparam"><span class="type"><a href="language.pseudo-types.html#language.types.mixed" class="type mixed">mixed</a></span> <code class="parameter">$value</code></span> )</div> <div class="methodsynopsis dc-description"> <span class="modifier">public</span> <span class="type">void</span> <span class="methodname"><a href="weakmap.offsetunset.html" class="methodname">offsetUnset</a></span> ( <span class="methodparam"><span class="type">object</span> <code class="parameter">$object</code></span> )</div> <div class="methodsynopsis dc-description"> <span class="modifier">public</span> <span class="type">void</span> <span class="methodname"><a href="weakmap.rewind.html" class="methodname">rewind</a></span> ( <span class="methodparam">void</span> )</div> <div class="methodsynopsis dc-description"> <span class="modifier">public</span> <span class="type">bool</span> <span class="methodname"><a href="weakmap.valid.html" class="methodname">valid</a></span> ( <span class="methodparam">void</span> )</div> }</div> </div> <div class="section" id="weakmap.examples"> <h2 class="title">Examples</h2> <p class="para"> <div class="example" id="example-553"> <p><strong>Example #1 <strong class="classname">Weakmap</strong> usage example</strong></p> <div class="example-contents"> <div class="phpcode"><code><span style="color: #000000"> <span style="color: #0000BB"><?php<br />$wm </span><span style="color: #007700">= new </span><span style="color: #0000BB">WeakMap</span><span style="color: #007700">();<br /><br /></span><span style="color: #0000BB">$o </span><span style="color: #007700">= new </span><span style="color: #0000BB">StdClass</span><span style="color: #007700">;<br /><br />class </span><span style="color: #0000BB">A </span><span style="color: #007700">{<br /> public function </span><span style="color: #0000BB">__destruct</span><span style="color: #007700">() {<br /> echo </span><span style="color: #DD0000">"Dead!\n"</span><span style="color: #007700">;<br /> }<br />}<br /><br /></span><span style="color: #0000BB">$wm</span><span style="color: #007700">[</span><span style="color: #0000BB">$o</span><span style="color: #007700">] = new </span><span style="color: #0000BB">A</span><span style="color: #007700">;<br /><br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">count</span><span style="color: #007700">(</span><span style="color: #0000BB">$wm</span><span style="color: #007700">));<br />echo </span><span style="color: #DD0000">"Unsetting..\n"</span><span style="color: #007700">;<br />unset(</span><span style="color: #0000BB">$o</span><span style="color: #007700">);<br />echo </span><span style="color: #DD0000">"Done\n"</span><span style="color: #007700">;<br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">count</span><span style="color: #007700">(</span><span style="color: #0000BB">$wm</span><span style="color: #007700">));</span> </span> </code></div> </div> <div class="example-contents"><p>The above example will output:</p></div> <div class="example-contents screen"> <div class="cdata"><pre> int(1) Unsetting.. Dead! Done int(0) </pre></div> </div> </div> </p> </div> </div> <h2>Table of Contents</h2><ul class="chunklist chunklist_reference"><li><a href="weakmap.construct.html">WeakMap::__construct</a> — Constructs a new map</li><li><a href="weakmap.count.html">WeakMap::count</a> — Counts the number of live entries in the map</li><li><a href="weakmap.current.html">WeakMap::current</a> — Returns the current value under iteration</li><li><a href="weakmap.key.html">WeakMap::key</a> — Returns the current key under iteration.</li><li><a href="weakmap.next.html">WeakMap::next</a> — Advances to the next map element</li><li><a href="weakmap.offsetexists.html">WeakMap::offsetExists</a> — Checks whether a certain object is in the map</li><li><a href="weakmap.offsetget.html">WeakMap::offsetGet</a> — Returns the value pointed to by a certain object</li><li><a href="weakmap.offsetset.html">WeakMap::offsetSet</a> — Updates the map with a new key-value pair</li><li><a href="weakmap.offsetunset.html">WeakMap::offsetUnset</a> — Removes an entry from the map</li><li><a href="weakmap.rewind.html">WeakMap::rewind</a> — Rewinds the iterator to the beginning of the map</li><li><a href="weakmap.valid.html">WeakMap::valid</a> — Returns whether the iterator is still on a valid map element</li></ul> </div> <hr /><div class="manualnavbar" style="text-align: center;"> <div class="prev" style="text-align: left; float: left;"><a href="weakref.valid.html">Weakref::valid</a></div> <div class="next" style="text-align: right; float: right;"><a href="weakmap.construct.html">WeakMap::__construct</a></div> <div class="up"><a href="book.weakref.html">Weakref</a></div> <div class="home"><a href="index.html">PHP Manual</a></div> </div></body></html>