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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"><html> <head> <title>Return the current key and value pair from an array and advance the array cursor</title> <meta http-equiv="content-type" content="text/html; charset=UTF-8"> </head> <body><div style="text-align: center;"> <div class="prev" style="text-align: left; float: left;"><a href="function.current.html">current</a></div> <div class="next" style="text-align: right; float: right;"><a href="function.end.html">end</a></div> <div class="up"><a href="ref.array.html">Array Functions</a></div> <div class="home"><a href="index.html">PHP Manual</a></div></div><hr /><div id="function.each" class="refentry"> <div class="refnamediv"> <h1 class="refname">each</h1> <p class="verinfo">(PHP 4, PHP 5)</p><p class="refpurpose"><span class="refname">each</span> — <span class="dc-title">Return the current key and value pair from an array and advance the array cursor</span></p> </div> <div class="refsect1 description"> <h3 class="title">Description</h3> <div class="methodsynopsis dc-description"> <span class="type">array</span> <span class="methodname"><b><b>each</b></b></span> ( <span class="methodparam"><span class="type">array</span> <tt class="parameter reference">&$array</tt></span> )</div> <p class="para rdfs-comment"> Return the current key and value pair from an array and advance the array cursor. </p> <p class="para"> After <b>each()</b> has executed, the array cursor will be left on the next element of the array, or past the last element if it hits the end of the array. You have to use <a href="function.reset.html" class="function">reset()</a> if you want to traverse the array again using each. </p> </div> <div class="refsect1 parameters"> <h3 class="title">Parameters</h3> <p class="para"> <dl> <dt> <span class="term"><i><tt class="parameter">array</tt></i></span> <dd> <p class="para"> The input array. </p> </dd> </dt> </dl> </p> </div> <div class="refsect1 returnvalues"> <h3 class="title">Return Values</h3> <p class="para"> Returns the current key and value pair from the array <i><tt class="parameter">array</tt></i>. This pair is returned in a four-element array, with the keys <i>0</i>, <i>1</i>, <i>key</i>, and <i>value</i>. Elements <i>0</i> and <i>key</i> contain the key name of the array element, and <i>1</i> and <i>value</i> contain the data. </p> <p class="para"> If the internal pointer for the array points past the end of the array contents, <b>each()</b> returns <b><tt>FALSE</tt></b>. </p> </div> <div class="refsect1 examples"> <h3 class="title">Examples</h3> <p class="para"> <div class="example"> <p><b>Example #1 <b>each()</b> examples</b></p> <div class="example-contents"><div class="phpcode"><code><span style="color: #000000"><span style="color: #0000BB"><?php<br />$foo </span><span style="color: #007700">= array(</span><span style="color: #DD0000">"bob"</span><span style="color: #007700">, </span><span style="color: #DD0000">"fred"</span><span style="color: #007700">, </span><span style="color: #DD0000">"jussi"</span><span style="color: #007700">, </span><span style="color: #DD0000">"jouni"</span><span style="color: #007700">, </span><span style="color: #DD0000">"egon"</span><span style="color: #007700">, </span><span style="color: #DD0000">"marliese"</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$bar </span><span style="color: #007700">= </span><span style="color: #0000BB">each</span><span style="color: #007700">(</span><span style="color: #0000BB">$foo</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">print_r</span><span style="color: #007700">(</span><span style="color: #0000BB">$bar</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?></span></span></code></div> </div> <div class="example-contents"><p> <var class="varname">$bar</var> now contains the following key/value pairs: </p></div> <div class="example-contents"><pre><div class="cdata"><pre>Array( [1] => bob [value] => bob [0] => 0 [key] => 0)</pre></div> </pre></div> </div> </p> <p class="para"> <div class="informalexample"> <div class="example-contents"><div class="phpcode"><code><span style="color: #000000"><span style="color: #0000BB"><?php<br />$foo </span><span style="color: #007700">= array(</span><span style="color: #DD0000">"Robert" </span><span style="color: #007700">=> </span><span style="color: #DD0000">"Bob"</span><span style="color: #007700">, </span><span style="color: #DD0000">"Seppo" </span><span style="color: #007700">=> </span><span style="color: #DD0000">"Sepi"</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$bar </span><span style="color: #007700">= </span><span style="color: #0000BB">each</span><span style="color: #007700">(</span><span style="color: #0000BB">$foo</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">print_r</span><span style="color: #007700">(</span><span style="color: #0000BB">$bar</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?></span></span></code></div> </div> <p class="para"> <var class="varname">$bar</var> now contains the following key/value pairs: </p> <div class="example-contents"><pre><div class="cdata"><pre>Array( [1] => Bob [value] => Bob [0] => Robert [key] => Robert)</pre></div> </pre></div> </div> </p> <p class="para"> <b>each()</b> is typically used in conjunction with <a href="function.list.html" class="function">list()</a> to traverse an array, here's an example: <div class="example"> <p><b>Example #2 Traversing an array with <b>each()</b></b></p> <div class="example-contents"><div class="phpcode"><code><span style="color: #000000"><span style="color: #0000BB"><?php<br />$fruit </span><span style="color: #007700">= array(</span><span style="color: #DD0000">'a' </span><span style="color: #007700">=> </span><span style="color: #DD0000">'apple'</span><span style="color: #007700">, </span><span style="color: #DD0000">'b' </span><span style="color: #007700">=> </span><span style="color: #DD0000">'banana'</span><span style="color: #007700">, </span><span style="color: #DD0000">'c' </span><span style="color: #007700">=> </span><span style="color: #DD0000">'cranberry'</span><span style="color: #007700">);<br /><br /></span><span style="color: #0000BB">reset</span><span style="color: #007700">(</span><span style="color: #0000BB">$fruit</span><span style="color: #007700">);<br />while (list(</span><span style="color: #0000BB">$key</span><span style="color: #007700">, </span><span style="color: #0000BB">$val</span><span style="color: #007700">) = </span><span style="color: #0000BB">each</span><span style="color: #007700">(</span><span style="color: #0000BB">$fruit</span><span style="color: #007700">)) {<br /> echo </span><span style="color: #DD0000">"$key => $val\n"</span><span style="color: #007700">;<br />}<br /></span><span style="color: #0000BB">?></span></span></code></div> </div> <div class="example-contents"><p>The above example will output:</p></div> <div class="example-contents"><pre><div class="cdata"><pre>a => appleb => bananac => cranberry</pre></div> </pre></div> </div> </p> <div class="caution"><b class="caution">Caution</b> <p class="para"> Because assigning an array to another variable resets the original arrays pointer, our example above would cause an endless loop had we assigned <var class="varname">$fruit</var> to another variable inside the loop. </p> </div> <div class="warning"><b class="warning">Warning</b> <p class="para"> <b>each()</b> will also accept objects, but may return unexpected results. Its therefore not recommeded to iterate though object properties with <b>each()</b>. </p> </div> </div> <div class="refsect1 seealso"> <h3 class="title">See Also</h3> <p class="para"> <ul class="simplelist"> <li class="member"><a href="function.key.html" class="function" rel="rdfs-seeAlso">key()</a></li> <li class="member"><a href="function.list.html" class="function" rel="rdfs-seeAlso">list()</a></li> <li class="member"><a href="function.current.html" class="function" rel="rdfs-seeAlso">current()</a></li> <li class="member"><a href="function.reset.html" class="function" rel="rdfs-seeAlso">reset()</a></li> <li class="member"><a href="function.next.html" class="function" rel="rdfs-seeAlso">next()</a></li> <li class="member"><a href="function.prev.html" class="function" rel="rdfs-seeAlso">prev()</a></li> <li class="member"><a href="control-structures.foreach.html" class="link">foreach</a></li> <li class="member"><a href="language.oop5.iterations.html" class="link">Object Iteration</a></li> </ul> </p> </div></div><hr /><div style="text-align: center;"> <div class="prev" style="text-align: left; float: left;"><a href="function.current.html">current</a></div> <div class="next" style="text-align: right; float: right;"><a href="function.end.html">end</a></div> <div class="up"><a href="ref.array.html">Array Functions</a></div> <div class="home"><a href="index.html">PHP Manual</a></div></div></body></html>⌨️ 快捷键说明
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