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</div><hr /><div id="function.sort" class="refentry">
<div class="refnamediv">
<h1 class="refname">sort</h1>
<p class="verinfo">(PHP 4, PHP 5)</p><p class="refpurpose"><span class="refname">sort</span> — <span class="dc-title">Sort an array</span></p>
</div>
<div class="refsect1 description" id="refsect1-function.sort-description">
<h3 class="title">Description</h3>
<div class="methodsynopsis dc-description">
<span class="type">bool</span> <span class="methodname"><strong>sort</strong></span>
( <span class="methodparam"><span class="type">array</span> <code class="parameter reference">&$array</code></span>
[, <span class="methodparam"><span class="type">int</span> <code class="parameter">$sort_flags</code><span class="initializer"> = SORT_REGULAR</span></span>
] )</div>
<p class="para rdfs-comment">
This function sorts an array. Elements will be arranged from
lowest to highest when this function has completed.
</p>
</div>
<div class="refsect1 parameters" id="refsect1-function.sort-parameters">
<h3 class="title">Parameters</h3>
<p class="para">
<dl>
<dt>
<span class="term"><em><code class="parameter">array</code></em></span>
<dd>
<p class="para">
The input array.
</p>
</dd>
</dt>
<dt>
<span class="term"><em><code class="parameter">sort_flags</code></em></span>
<dd>
<p class="para">
The optional second parameter <em><code class="parameter">sort_flags</code></em>
may be used to modify the sorting behavior using these values:
</p>
<p class="para">
Sorting type flags:
<ul class="itemizedlist">
<li class="listitem">
<span class="simpara"><strong><code>SORT_REGULAR</code></strong> - compare items normally
(don't change types)</span>
</li>
<li class="listitem">
<span class="simpara"><strong><code>SORT_NUMERIC</code></strong> - compare items numerically</span>
</li>
<li class="listitem">
<span class="simpara"><strong><code>SORT_STRING</code></strong> - compare items as strings</span>
</li>
<li class="listitem">
<span class="simpara">
<strong><code>SORT_LOCALE_STRING</code></strong> - compare items as
strings, based on the current locale. It uses the locale,
which can be changed using <span class="function"><a href="function.setlocale.html" class="function">setlocale()</a></span>
</span>
</li>
<li class="listitem">
<span class="simpara">
<strong><code>SORT_NATURAL</code></strong> - compare items as strings
using "natural ordering" like <span class="function"><a href="function.natsort.html" class="function">natsort()</a></span>
</span>
</li>
<li class="listitem">
<span class="simpara">
<strong><code>SORT_FLAG_CASE</code></strong> - can be combined
(bitwise OR) with
<strong><code>SORT_STRING</code></strong> or
<strong><code>SORT_NATURAL</code></strong> to sort strings case-insensitively
</span>
</li>
</ul>
</p>
</dd>
</dt>
</dl>
</p>
</div>
<div class="refsect1 returnvalues" id="refsect1-function.sort-returnvalues">
<h3 class="title">Return Values</h3>
<p class="para">
Returns <strong><code>TRUE</code></strong> on success or <strong><code>FALSE</code></strong> on failure.
</p>
</div>
<div class="refsect1 changelog" id="refsect1-function.sort-changelog">
<h3 class="title">Changelog</h3>
<table class="doctable informaltable">
<thead>
<tr>
<th>Version</th>
<th>Description</th>
</tr>
</thead>
<tbody class="tbody">
<tr>
<td>5.4.0</td>
<td>
Added support for <strong><code>SORT_NATURAL</code></strong> and
<strong><code>SORT_FLAG_CASE</code></strong> as <em><code class="parameter">sort_flags</code></em>
</td>
</tr>
<tr>
<td>5.0.2</td>
<td>
Added <strong><code>SORT_LOCALE_STRING</code></strong>
</td>
</tr>
</tbody>
</table>
</div>
<div class="refsect1 examples" id="refsect1-function.sort-examples">
<h3 class="title">Examples</h3>
<p class="para">
<div class="example" id="example-5032">
<p><strong>Example #1 <span class="function"><strong>sort()</strong></span> example</strong></p>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br /><br />$fruits </span><span style="color: #007700">= array(</span><span style="color: #DD0000">"lemon"</span><span style="color: #007700">, </span><span style="color: #DD0000">"orange"</span><span style="color: #007700">, </span><span style="color: #DD0000">"banana"</span><span style="color: #007700">, </span><span style="color: #DD0000">"apple"</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">sort</span><span style="color: #007700">(</span><span style="color: #0000BB">$fruits</span><span style="color: #007700">);<br />foreach (</span><span style="color: #0000BB">$fruits </span><span style="color: #007700">as </span><span style="color: #0000BB">$key </span><span style="color: #007700">=> </span><span style="color: #0000BB">$val</span><span style="color: #007700">) {<br /> echo </span><span style="color: #DD0000">"fruits[" </span><span style="color: #007700">. </span><span style="color: #0000BB">$key </span><span style="color: #007700">. </span><span style="color: #DD0000">"] = " </span><span style="color: #007700">. </span><span style="color: #0000BB">$val </span><span style="color: #007700">. </span><span style="color: #DD0000">"\n"</span><span style="color: #007700">;<br />}<br /><br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
<div class="example-contents"><p>The above example will output:</p></div>
<div class="example-contents screen">
<div class="cdata"><pre>
fruits[0] = apple
fruits[1] = banana
fruits[2] = lemon
fruits[3] = orange
</pre></div>
</div>
</div>
</p>
<p class="para">
The fruits have been sorted in alphabetical order.
</p>
<p class="para">
<div class="example" id="example-5033">
<p><strong>Example #2 <span class="function"><strong>sort()</strong></span> example using case-insensitive natural
ordering</strong></p>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br /><br />$fruits </span><span style="color: #007700">= array(<br /> </span><span style="color: #DD0000">"Orange1"</span><span style="color: #007700">, </span><span style="color: #DD0000">"orange2"</span><span style="color: #007700">, </span><span style="color: #DD0000">"Orange3"</span><span style="color: #007700">, </span><span style="color: #DD0000">"orange20"<br /></span><span style="color: #007700">);<br /></span><span style="color: #0000BB">sort</span><span style="color: #007700">(</span><span style="color: #0000BB">$fruits</span><span style="color: #007700">, </span><span style="color: #0000BB">SORT_NATURAL </span><span style="color: #007700">| </span><span style="color: #0000BB">SORT_FLAG_CASE</span><span style="color: #007700">);<br />foreach (</span><span style="color: #0000BB">$fruits </span><span style="color: #007700">as </span><span style="color: #0000BB">$key </span><span style="color: #007700">=> </span><span style="color: #0000BB">$val</span><span style="color: #007700">) {<br /> echo </span><span style="color: #DD0000">"fruits[" </span><span style="color: #007700">. </span><span style="color: #0000BB">$key </span><span style="color: #007700">. </span><span style="color: #DD0000">"] = " </span><span style="color: #007700">. </span><span style="color: #0000BB">$val </span><span style="color: #007700">. </span><span style="color: #DD0000">"\n"</span><span style="color: #007700">;<br />}<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 screen">
<div class="cdata"><pre>
fruits[0] = Orange1
fruits[1] = orange2
fruits[2] = Orange3
fruits[3] = orange20
</pre></div>
</div>
</div>
</p>
<p class="para">
The fruits have been sorted like <span class="function"><a href="function.natcasesort.html" class="function">natcasesort()</a></span>.
</p>
</div>
<div class="refsect1 notes" id="refsect1-function.sort-notes">
<h3 class="title">Notes</h3>
<blockquote class="note"><p><strong class="note">Note</strong>: <span class="simpara">This function
assigns new keys to the elements in <em><code class="parameter">array</code></em>.
It will remove any existing keys that may have been assigned, rather
than just reordering the keys.</span></p></blockquote>
<blockquote class="note"><p><strong class="note">Note</strong>:
<span class="simpara">
Like most PHP sorting functions, <span class="function"><strong>sort()</strong></span> uses an
implementation of <a href="http://en.wikipedia.org/wiki/Quicksort" class="link external">» Quicksort</a>.
The pivot is chosen in the middle of the partition resulting in an optimal
time for already sorted arrays. This is however an implementation detail you
shouldn't rely on.
</span>
</p></blockquote>
<div class="warning"><strong class="warning">Warning</strong>
<p class="simpara">
Be careful when sorting arrays with mixed types values because
<span class="function"><strong>sort()</strong></span> can produce unpredictable results.
</p>
</div>
</div>
<div class="refsect1 seealso" id="refsect1-function.sort-seealso">
<h3 class="title">See Also</h3>
<p class="para">
<ul class="simplelist">
<li class="member"> <span class="function"><a href="function.asort.html" class="function" rel="rdfs-seeAlso">asort()</a> - Sort an array and maintain index association</span></li>
<li class="member">The <a href="array.sorting.html" class="link">comparison of array sorting functions</a></li>
</ul>
</p>
</div>
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