What's wrong in my autoload code

Question

I did test both of codes to autoload Classes to page,But not work for me!

What's wrong ?

spl_autoload_extensions('.php, .class.php');
    spl_autoload_register(function ($name){
        if('inc/'."{$name}".'.class.php'){
            require('inc/'."{$name}".'.class.php');
        }
    });

AND :

class FW{
        public static function autoload($class){
            $class = strtolower($class);
            $fpath = realpath(dirname(__FILE__)).'/inc/'."{$class}". '.class.php';
            if(is_readable($fpath)){
                require_once($fpath);
            }
        }
    }

    spl_autoload_register('FW::autoload');

Answer 1

As my question have not answer I reply answer and hope it will be useful. I add the code to Config.php and edit classes name style form whatever.class.php to class.whatever.php and it's work for me.

    //  Classes Autoloader
    spl_autoload_extensions('.php, .class.php');
    spl_autoload_register(function ($name){
        if(is_readable(realpath(dirname(__FILE__)).'/inc/class.'."{$name}".'.php')){
            require(realpath(dirname(__FILE__)).'/inc/class.'."{$name}".'.php');
        }
    });