Example #1 Autoload example
This example attempts to load the classes MyClass1 and MyClass2 from the files MyClass1.php and MyClass2.php respectively.
<?php
spl_autoload_register(function ($class_name) {
    include $class_name . '.php';
});
$obj  = new MyClass1();
$obj2 = new MyClass2(); 
?>

The introduction of spl_autoload_register() gave programmers
the ability to create an autoload chain,
a series of functions that can be called to try and load a class or interface.
For example:
<?php
function autoloadModel($className) { $filename = "models/" . $className . ".php"; if (is_readable($filename)) { require $filename; }
}
function autoloadController($className) { $filename = "controllers/" . $className . ".php"; if (is_readable($filename)) { require $filename; }
}
spl_autoload_register("autoloadModel");
spl_autoload_register("autoloadController");

<?php
//custom autoload without composer
$to_map = [ 'App\\' => 'app/', 'Core\\' => 'Core/',
];
foreach($to_map as $prefix => $base_dir)
{ spl_autoload_register(function ($class) use ($prefix, $base_dir) { $base_dir = __DIR__ . "/{$base_dir}"; $len = strlen($prefix); if (strncmp($prefix, $class, $len) !== 0) { return; } $relative_class = substr($class, $len); $file = $base_dir . str_replace('\\', '/', $relative_class) . '.php'; if (file_exists($file)) { require $file; } });
}

require 'vendor/autoload.php';