在类中实现__autoload

Question

Is there a way I can define __autoload in a class, so whenever I access an undefined class PHP will run the __autoload class method?

<?php 
class Test {
    public function __construct() {
        echo 'Instantiating ', __CLASS__, "
";
    }

    public function __autoload($className) {
        echo "Loading $className
";
        require_once($className . '.php');
    }

    public function test() {
        $test = new AnotherClass();
    }
}

$bill = new Test();
$bill->test();

AnotherClass.php:

<?php
class AnotherClass {
    public function __construct() {
        echo 'Instantiating ', __CLASS__, "
";
    }
}

Output:

Instantiating Test
Loading AnotherClass
Instantiating AnotherClass

Answer 1

No, the __autoload function must be global.

However, SPL has a way to register any callable as an autoload function: spl_autoload_register(). It does not make much sense to use a class method though - you'd probably just create the instance, register the method and never use that instance again.