mirror of
https://github.com/sigmasternchen/php-doc-en
synced 2025-03-19 02:18:56 +00:00
04077dd209
git-svn-id: https://svn.php.net/repository/phpdoc/en/trunk@283798 c90b9560-bf6c-de11-be94-00142212c4b1
118 lines
3.1 KiB
XML
118 lines
3.1 KiB
XML
<?xml version="1.0" encoding="iso-8859-1"?>
|
|
<!-- $Revision$ -->
|
|
<sect1 xml:id="language.oop5.autoload" xmlns="http://docbook.org/ns/docbook">
|
|
<title>Autoloading Objects</title>
|
|
<para>
|
|
Many developers writing object-oriented applications create
|
|
one PHP source file per-class definition. One of the biggest
|
|
annoyances is having to write a long list of needed includes
|
|
at the beginning of each script (one for each class).
|
|
</para>
|
|
<para>
|
|
In PHP 5, this is no longer necessary. You may define an
|
|
__autoload function which is automatically
|
|
called in case you are trying to use a class/interface which hasn't been
|
|
defined yet. By calling this function the scripting engine is given
|
|
a last chance to load the class before PHP fails with an error.
|
|
</para>
|
|
<note>
|
|
<para>
|
|
Exceptions thrown in __autoload function cannot be caught in the
|
|
<link linkend="language.exceptions">catch</link> block and results in
|
|
a fatal error.
|
|
</para>
|
|
</note>
|
|
<note>
|
|
<para>
|
|
Autoloading is not available if using PHP in CLI
|
|
<link linkend="features.commandline">interactive mode</link>.
|
|
</para>
|
|
</note>
|
|
<note>
|
|
<para>
|
|
If the class name is used e.g. in <function>call_user_func</function> then
|
|
it can contain some dangerous characters such as <literal>../</literal>.
|
|
It is recommended to not use the user-input in such functions or at least
|
|
verify the input in <function>__autoload</function>.
|
|
</para>
|
|
</note>
|
|
<para>
|
|
<example>
|
|
<title>Autoload example</title>
|
|
<para>
|
|
This example attempts to load the classes <literal>MyClass1</literal>
|
|
and <literal>MyClass2</literal> from the files <filename>MyClass1.php</filename>
|
|
and <filename>MyClass2.php</filename> respectively.
|
|
</para>
|
|
<programlisting role="php">
|
|
<![CDATA[
|
|
<?php
|
|
function __autoload($class_name) {
|
|
require_once $class_name . '.php';
|
|
}
|
|
|
|
$obj = new MyClass1();
|
|
$obj2 = new MyClass2();
|
|
?>
|
|
]]>
|
|
</programlisting>
|
|
</example>
|
|
<example>
|
|
<title>Autoload other example</title>
|
|
<para>
|
|
This example attempts to load the interface <literal>ITest</literal>.
|
|
</para>
|
|
<programlisting role="php">
|
|
<![CDATA[
|
|
<?php
|
|
|
|
function __autoload($name) {
|
|
var_dump($name);
|
|
}
|
|
|
|
class Foo implements ITest {
|
|
}
|
|
|
|
/*
|
|
string(5) "ITest"
|
|
|
|
Fatal error: Interface 'ITest' not found in ...
|
|
*/
|
|
?>
|
|
]]>
|
|
</programlisting>
|
|
</example>
|
|
</para>
|
|
|
|
<simplesect role="seealso">
|
|
&reftitle.seealso;
|
|
<para>
|
|
<simplelist>
|
|
<member><function>unserialize</function></member>
|
|
<member><link linkend="unserialize-callback-func">unserialize_callback_func</link></member>
|
|
</simplelist>
|
|
</para>
|
|
</simplesect>
|
|
|
|
</sect1>
|
|
|
|
<!-- Keep this comment at the end of the file
|
|
Local variables:
|
|
mode: sgml
|
|
sgml-omittag:t
|
|
sgml-shorttag:t
|
|
sgml-minimize-attributes:nil
|
|
sgml-always-quote-attributes:t
|
|
sgml-indent-step:1
|
|
sgml-indent-data:t
|
|
indent-tabs-mode:nil
|
|
sgml-parent-document:nil
|
|
sgml-default-dtd-file:"../../manual.ced"
|
|
sgml-exposed-tags:nil
|
|
sgml-local-catalogs:nil
|
|
sgml-local-ecat-files:nil
|
|
End:
|
|
vim600: syn=xml fen fdm=syntax fdl=2 si
|
|
vim: et tw=78 syn=sgml
|
|
vi: ts=1 sw=1
|
|
-->
|