autoloader-2.php

<?php
spl_autoload_register('autoLoader');

function autoLoader($className) {
  $url = $_SERVER['HTTP_HOST'].$_SERVER['REQUEST_URI'];
  if (strpos($url, 'inc')) {
    $path = '../classes/';
  } else {
    $path = 'classes/';
  }
  $ext = '.class.php';
  require_once $path . $className . $ext;
}

simple-autoloader.php

<?php
spl_autoload_register('autoLoader');

function autoLoader($className) {
  $path = 'classes/';
  $ext = './class.php';
  require_once $path . $className . $ext;
}