php __autoload function

__autoload(string $className) — Attempt to load undefined class

This autoload function call when we will try to create instance of undefined class.

Like here we don’t have class A in index.php. If in index.php file we don’t have __autoload function

We will can get error. But because of this function we can load file for class A

index.php

<?phpfunction __autoload($className){    $filename = "./". $className .".php";    include_once($filename);}

$obj = new A();?>

A.php

<?php class A { public function __construct() { echo "TEST"; return $this } }?>