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spl_autoload_extensions

(PHP 5 >= 5.1.0, PHP 7, PHP 8)

spl_autoload_extensionsRegister and return default file extensions for spl_autoload

Description

spl_autoload_extensions(?string $file_extensions = null): string

This function can modify and check the file extensions that the built in __autoload() fallback function spl_autoload() will be using.

Note: There should not be a space between the defined file extensions.

Parameters

file_extensions

If null, it simply returns the current list of extensions each separated by comma. To modify the list of file extensions, simply invoke the functions with the new list of file extensions to use in a single string with each extensions separated by comma.

Return Values

A comma delimited list of default file extensions for spl_autoload().

Changelog

Version Description
8.0.0 file_extensions is now nullable.

Examples

Example #1 spl_autoload_extensions() example

<?php
spl_autoload_extensions
(".php,.inc");
?>
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User Contributed Notes 2 notes

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6
dantedantas at gmail dot com
7 years ago
The order of the extensions influence the velocity of the reply. For example:

spl_autoload_extensions(".php, .inc");

is more fast than:

spl_autoload_extensions(".inc, .php");

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
?>
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3
pim dot stoit at gmail dot com
8 years ago
Extensions doesn't have to start with a dot, spl_autload() will simply append whatever you supply to the basename. The following example will try to load "test.php" first, and "test/index.php" as well:

spl_autoload_register('.php,/index.php');
spl_autoload('Test');
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