PHP Doku:: Default implementation for __autoload() - function.spl-autoload.html

Verlauf / Chronik / History: (1) anzeigen

Sie sind hier:
Doku-StartseitePHP-HandbuchFunktionsreferenzSonstige GrunderweiterungenStandard PHP Library (SPL)SPL Funktionenspl_autoload

Ein Service von Reinhard Neidl - Webprogrammierung.

SPL Funktionen

<<spl_autoload_unregister

spl_classes>>

spl_autoload

(PHP 5 >= 5.1.2)

spl_autoloadDefault implementation for __autoload()

Beschreibung

void spl_autoload ( string $class_name [, string $file_extensions = spl_autoload_extensions() ] )

This function is intended to be used as a default implementation for __autoload(). If nothing else is specified and spl_autoload_register() is called without any parameters then this functions will be used for any later call to __autoload().

Parameter-Liste

class_name

file_extensions

By default it checks all include paths to contain filenames built up by the lowercase class name appended by the filename extensions .inc and .php.

Rückgabewerte

Es wird kein Wert zurückgegeben.


3 BenutzerBeiträge:
- Beiträge aktualisieren...
daniel
6.07.2010 4:58
Note this function will LOWERCASE the class names its looking for, dont be confused when it cant find Foo_Bar.php

also, unlike most other autoloader code snippets, this function DOES NOT translate underscores to slashes.

class Foo_Bar {}
will load foo_bar.php and will not try to load foo/bar.php

You can get around this with
spl_autoload_register(function($class) { return spl_autoload(str_replace('_', '/', $class));});
simast at gmail dot com
8.08.2009 7:22
Note, that the default autoload implementation is written in C land and is always slightly faster then your native PHP one.

Here is a trick to use default implementation with any configuration:

<?php

   
// Your custom class dir
   
define('CLASS_DIR', 'class/')

   
// Add your class dir to include path
   
set_include_path(get_include_path().PATH_SEPARATOR.CLASS_DIR);

   
// You can use this trick to make autoloader look for commonly used "My.class.php" type filenames
   
spl_autoload_extensions('.class.php');

   
// Use default autoload implementation
   
spl_autoload_register();
?>

This also works with namespaces out of the box. So you can write code like "use My\Name\Object" and it will map to "class/My/Name/Object.class.php" file path!
safak_ozpinar at NOSPAM dot yahoo dot com
26.09.2007 4:17
Note that, the orders of file extensions is important for performance. You should make the priority of your favourite file extension higest or use only one extension for your class files. Check out this example:

Some class files:

ClassA.php
<?php class ClassA { var $val = 'Hello from class "ClassA"'; } ?>
ClassB.php
<?php class ClassB { var $val = 'Hello from class "ClassB"'; } ?>
ClassC.php
<?php class ClassC { var $val = 'Hello from class "ClassC"'; } ?>
ClassD.php
<?php class ClassD { var $val = 'Hello from class "ClassD"'; } ?>
ClassE.php
<?php class ClassE { var $val = 'Hello from class "ClassE"'; } ?>

1. Simple:
<?php
// default priority: .inc .php
for($n=65; $n<70; $n++) {
   
$className = 'Class'.chr($n);
   
spl_autoload($className);
   
$ins = new $className;
    echo
$ins->val.'<br>';
}
// 4.2 miliseconds
?>

2. Change priority:
<?php
spl_autoload_extensions
('.php,.inc');
// new priority: .php .inc
for($n=65; $n<70; $n++) {
   
$className = 'Class'.chr($n);
   
spl_autoload($className);
   
$ins = new $className;
    echo
$ins->val.'<br>';
}
// 1.4 miliseconds
?>

Or you can use this simple function that runs a bit faster for the extensions with lower priority :)
<?php
function my_autoload($className, $extList='.inc,.php') {
   
$ext = explode(',',$extList);
    foreach(
$ext as $x) {
       
$fname = $className.$x;
        if(@
file_exists($fname)) {
            require_once(
$fname);
            return
true;
        }
    }
    return
false;
}

for(
$n=65; $n<70; $n++) {
   
$className = 'Class'.chr($n);
   
my_autoload($className);
   
$ins = new $className;
    echo
$ins->val.'<br>';
}
// 2.6 miliseconds
?>
---
Safak Ozpinar - Istanbul University, Computer Engineering



PHP Powered Diese Seite bei php.net
The PHP manual text and comments are covered by the Creative Commons Attribution 3.0 License © the PHP Documentation Group - Impressum - mail("TO:Reinhard Neidl",...)