php-doc-en/reference/array/functions/current.xml

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<?xml version="1.0" encoding="utf-8"?>
<!-- $Revision$ -->
<refentry xml:id="function.current" xmlns="http://docbook.org/ns/docbook">
<refnamediv>
<refname>current</refname>
<refpurpose>Return the current element in an array</refpurpose>
</refnamediv>
<refsect1 role="description">
&reftitle.description;
<methodsynopsis>
<type>mixed</type><methodname>current</methodname>
<methodparam><type>array</type><parameter>array</parameter></methodparam>
</methodsynopsis>
<para>
Every array has an internal pointer to its "current" element,
which is initialized to the first element inserted into the
array.
</para>
</refsect1>
<refsect1 role="parameters">
&reftitle.parameters;
<para>
<variablelist>
<varlistentry>
<term><parameter>array</parameter></term>
<listitem>
<para>
The array.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>
</refsect1>
<refsect1 role="returnvalues">
&reftitle.returnvalues;
<para>
The <function>current</function> function simply returns the
value of the array element that's currently being pointed to by the
internal pointer. It does not move the pointer in any way. If the
internal pointer points beyond the end of the elements list or the array is
empty, <function>current</function> returns &false;.
</para>
&return.falseproblem;
</refsect1>
<refsect1 role="changelog">
&reftitle.changelog;
<para>
<informaltable>
<tgroup cols="2">
<thead>
<row>
<entry>&Version;</entry>
<entry>&Description;</entry>
</row>
</thead>
<tbody>
<row>
<entry>7.0.0</entry>
<entry>
<parameter>array</parameter> is now always passed by value.
Prior to this version, it was passed by reference if possible,
and by value otherwise.
</entry>
</row>
</tbody>
</tgroup>
</informaltable>
</para>
</refsect1>
<refsect1 role="examples">
&reftitle.examples;
<para>
<example>
<title>Example use of <function>current</function> and friends</title>
<programlisting role="php">
<![CDATA[
<?php
$transport = array('foot', 'bike', 'car', 'plane');
$mode = current($transport); // $mode = 'foot';
$mode = next($transport); // $mode = 'bike';
$mode = current($transport); // $mode = 'bike';
$mode = prev($transport); // $mode = 'foot';
$mode = end($transport); // $mode = 'plane';
$mode = current($transport); // $mode = 'plane';
$arr = array();
var_dump(current($arr)); // bool(false)
$arr = array(array());
var_dump(current($arr)); // array(0) { }
?>
]]>
</programlisting>
</example>
</para>
</refsect1>
<refsect1 role="notes">
&reftitle.notes;
<note>
<simpara>
The results of calling <function>current</function> on an empty array
and on an array, whose internal pointer points beyond the end of the elements,
are indistinguishable from a <type>boolean</type> &false; element.
To properly traverse an array which may contain &false; elements, see the
<function>foreach</function> function.
</simpara>
<simpara>
To still use <function>current</function> and properly check if the value
is really an element of the array, the <function>key</function>
of the <function>current</function> element should be checked to be strictly
different from &null;.
</simpara>
</note>
</refsect1>
<refsect1 role="seealso">
&reftitle.seealso;
<para>
<simplelist>
<member><function>end</function></member>
<member><function>key</function></member>
<member><function>each</function></member>
<member><function>prev</function></member>
<member><function>reset</function></member>
<member><function>next</function></member>
</simplelist>
</para>
</refsect1>
</refentry>
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