spl_autoload_extensions

(PHP 5 >= 5.1.2, PHP 7)

spl_autoload_extensions — 注册并返回spl_autoload函数使用的默认文件扩展名。

说明

string spl_autoload_extensions ([ string $file_extensions ] )

本函数用来修改和检查 __autoload() 函数内置的默认实现函数 spl_autoload() 所使用的扩展名。

参数

file_extensions

当不使用任何参数调用此函数时，它返回当前的文件扩展名的列表，不同的扩展名用逗号分隔。要修改文件扩展名列表，用一个逗号分隔的新的扩展名列表字符串来调用本函数即可。中文注：默认的spl_autoload函数使用的扩展名是".inc,.php"。

返回值

逗号分隔的spl_autoload()函数的默认文件扩展名。

User Contributed Notes

dantedantas at gmail dot com 05-Jul-2017 06:46
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
?>
pim dot stoit at gmail dot com 10-May-2016 03:00
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');
Jeremy Cook 03-Sep-2010 03:46
A quick note for anyone using this function to add their own autoload extensions. I found that if I included a space in between the different extensions (i.e. '.php, .class.php') the function would not work. To get it to work I had to remove the spaces between the extensions (ie. '.php,.class.php'). This was tested in PHP 5.3.3 on Windows and I'm using spl_autoload_register() without adding any custom autoload functions.

Hope that helps somebody.
Kerry Kobashi 12-May-2010 02:50
Extensions include the period. For example:

spl_autoload_extensions(".inc,.php,.lib,.lib.php");