Autoloading Problem in Object-Oriented PHP Program - php

Question

Good afternoon to everyone.
For the past 3 days, I've been struggling with PHP's Autoloading features, which aims to simplify and unify a program's class files, all located in one executing file. For the context, I am currently learning the OOP perspective of PHP from this tutorial videos to not only further understand PHP's OOP understanding before doing a PHP OOP project from college, but also to try to create my own PHP program, so do ELI5 about the solution to me, please.
From what I've learned from the following videos: Video 1 and Video 2, the autoload codes I written from what I've learned appears to work fine, however, it gave two warnings:
Warning: include(/classes/person.php): failed to open stream: No such file or directory in C:\xampp\htdocs\CollegeTimetableApp\includes\autoloader.php on line 12
Warning: include(): Failed opening '/classes/person.php' for inclusion (include_path='C:\xampp\php\PEAR') in C:\xampp\htdocs\CollegeTimetableApp\includes\autoloader.php on line 12
And, it gave a fatal error message as follows:
Fatal error: Uncaught Error: Class 'person' not found in C:\xampp\htdocs\CollegeTimetableApp\includes\index.php:33 Stack trace: #0 {main} thrown in C:\xampp\htdocs\CollegeTimetableApp\includes\index.php on line 33
I will include downloadable files so that anyone check and verify it with me.
The Autoloader codes on the autoloading file:
<?php
spl_autoload_register(function($className) {
include str_replace("\\","/","\classes").'/'.str_replace('\\',"/",$className).'.php';
});
?>
Simple executing codes on the index file:
<?php
$person1 = new person();
$person1->SetName("Kai");
echo $person1->name;
?>
My questions: what's wrong, how to create a functioning autoload feature, and are there any additional corrections that can be made from my program?
Thank you.

Answer 1

Try including $_SERVER['DOCUMENT_ROOT'] to your path, as well as the sub folder in that folderwhich contains your app.
<?php
spl_autoload_register(function($className) {
$file = $_SERVER['DOCUMENT_ROOT']; // This is the folder you serve files from
$file .= '/CollegeTimetableApp' // This is the folder in which your app lives
$file .= str_replace("\\", "/", "\classes");
$file .= '/'; // Consider using DIRECTORY_SEPARATOR instead
$file .= str_replace('\\', "/", $className);
$file .= '.php';
include $file;
});
?>