Define php5 autoload behaviour, Closes bug #28333. And Example.

git-svn-id: https://svn.php.net/repository/phpdoc/en/trunk@162510 c90b9560-bf6c-de11-be94-00142212c4b1
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Curt Zirzow 2004-07-02 03:03:52 +00:00
parent 950287b897
commit 1836f1a4cc

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@ -1,5 +1,5 @@
<?xml version="1.0" encoding="iso-8859-1"?>
<!-- $Revision: 1.3 $ -->
<!-- $Revision: 1.4 $ -->
<!-- splitted from ./en/functions/classobj.xml, last change in rev 1.11 -->
<refentry id="function.class-exists">
<refnamediv>
@ -11,12 +11,48 @@
<methodsynopsis>
<type>bool</type><methodname>class_exists</methodname>
<methodparam><type>string</type><parameter>class_name</parameter></methodparam>
<methodparam choice="opt"><type>bool</type><parameter>autoload</parameter></methodparam>
</methodsynopsis>
<note>
<para>
The <parameter>autoload</parameter> parameter was added in PHP 5
</para>
</note>
<para>
This function returns &true; if the class given by
<parameter>class_name</parameter> has been defined,
&false; otherwise.
</para>
<para>
<function>class_exists</function> will attempt to call __autoload by
default, if you don't want <function>class_exists</function> to
call __autoload(), you can set the paramater <parameter>autoload</parameter>
to &false;.
</para>
<para>
<example>
<title><parameter>autoload</parameter> parameter example</title>
<programlisting role="php">
<![CDATA[
<?php
function __autoload($class) {
include($class . '.php');
/* Check to see it the include defined the class */
if ( !class_exists($class, false) ) {
trigger_error("Unable to load class $class", E_USER_ERROR);
}
}
if( class_exists('MyClass') ) {
$myclass = new MyClass();
}
?>
]]>
</programlisting>
</example>
</para>
<simpara>
See also <function>get_declared_classes</function>.
</simpara>