<!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>Call a function for every element in an iterator</title> </head> <body><div class="manualnavbar" style="text-align: center;"> <div class="prev" style="text-align: left; float: left;"><a href="function.class-uses.html">class_uses</a></div> <div class="next" style="text-align: right; float: right;"><a href="function.iterator-count.html">iterator_count</a></div> <div class="up"><a href="ref.spl.html">SPL Functions</a></div> <div class="home"><a href="index.html">PHP Manual</a></div> </div><hr /><div id="function.iterator-apply" class="refentry"> <div class="refnamediv"> <h1 class="refname">iterator_apply</h1> <p class="verinfo">(PHP 5 >= 5.1.0)</p><p class="refpurpose"><span class="refname">iterator_apply</span> — <span class="dc-title">Call a function for every element in an iterator</span></p> </div> <div class="refsect1 description" id="refsect1-function.iterator-apply-description"> <h3 class="title">Description</h3> <div class="methodsynopsis dc-description"> <span class="type">int</span> <span class="methodname"><strong>iterator_apply</strong></span> ( <span class="methodparam"><span class="type"><a href="class.traversable.html" class="type Traversable">Traversable</a></span> <code class="parameter">$iterator</code></span> , <span class="methodparam"><span class="type"><a href="language.types.callable.html" class="type callable">callable</a></span> <code class="parameter">$function</code></span> [, <span class="methodparam"><span class="type">array</span> <code class="parameter">$args</code></span> ] )</div> <p class="para rdfs-comment"> Calls a function for every element in an iterator. </p> </div> <div class="refsect1 parameters" id="refsect1-function.iterator-apply-parameters"> <h3 class="title">Parameters</h3> <p class="para"> <dl> <dt> <span class="term"><em><code class="parameter">iterator</code></em></span> <dd> <p class="para"> The class to iterate over. </p> </dd> </dt> <dt> <span class="term"><em><code class="parameter">function</code></em></span> <dd> <p class="para"> The callback function to call on every element. <blockquote class="note"><p><strong class="note">Note</strong>: <span class="simpara"> The function must return <strong><code>TRUE</code></strong> in order to continue iterating over the <em><code class="parameter">iterator</code></em>. </span> </p></blockquote> </p> </dd> </dt> <dt> <span class="term"><em><code class="parameter">args</code></em></span> <dd> <p class="para"> Arguments to pass to the callback function. </p> </dd> </dt> </dl> </p> </div> <div class="refsect1 returnvalues" id="refsect1-function.iterator-apply-returnvalues"> <h3 class="title">Return Values</h3> <p class="para"> Returns the iteration count. </p> </div> <div class="refsect1 examples" id="refsect1-function.iterator-apply-examples"> <h3 class="title">Examples</h3> <p class="para"> <div class="example" id="example-3915"> <p><strong>Example #1 <span class="function"><strong>iterator_apply()</strong></span> example</strong></p> <div class="example-contents"> <div class="phpcode"><code><span style="color: #000000"> <span style="color: #0000BB"><?php<br /></span><span style="color: #007700">function </span><span style="color: #0000BB">print_caps</span><span style="color: #007700">(</span><span style="color: #0000BB">Iterator $iterator</span><span style="color: #007700">) {<br /> echo </span><span style="color: #0000BB">strtoupper</span><span style="color: #007700">(</span><span style="color: #0000BB">$iterator</span><span style="color: #007700">-></span><span style="color: #0000BB">current</span><span style="color: #007700">()) . </span><span style="color: #DD0000">"\n"</span><span style="color: #007700">;<br /> return </span><span style="color: #0000BB">TRUE</span><span style="color: #007700">;<br />}<br /><br /></span><span style="color: #0000BB">$it </span><span style="color: #007700">= new </span><span style="color: #0000BB">ArrayIterator</span><span style="color: #007700">(array(</span><span style="color: #DD0000">"Apples"</span><span style="color: #007700">, </span><span style="color: #DD0000">"Bananas"</span><span style="color: #007700">, </span><span style="color: #DD0000">"Cherries"</span><span style="color: #007700">));<br /></span><span style="color: #0000BB">iterator_apply</span><span style="color: #007700">(</span><span style="color: #0000BB">$it</span><span style="color: #007700">, </span><span style="color: #DD0000">"print_caps"</span><span style="color: #007700">, array(</span><span style="color: #0000BB">$it</span><span style="color: #007700">));<br /></span><span style="color: #0000BB">?></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> APPLES BANANAS CHERRIES </pre></div> </div> </div> </p> </div> <div class="refsect1 seealso" id="refsect1-function.iterator-apply-seealso"> <h3 class="title">See Also</h3> <p class="para"> <ul class="simplelist"> <li class="member"> <span class="function"><a href="function.array-walk.html" class="function" rel="rdfs-seeAlso">array_walk()</a> - Apply a user function to every member of an array</span></li> </ul> </p> </div> </div><hr /><div class="manualnavbar" style="text-align: center;"> <div class="prev" style="text-align: left; float: left;"><a href="function.class-uses.html">class_uses</a></div> <div class="next" style="text-align: right; float: right;"><a href="function.iterator-count.html">iterator_count</a></div> <div class="up"><a href="ref.spl.html">SPL Functions</a></div> <div class="home"><a href="index.html">PHP Manual</a></div> </div></body></html>