spl_autoload_register无法获得“使用”命名空间

Question

#file1
spl_autoload_register(function($class){
    require_once "{$class}.php";
});

new classes\Foo();

#file2
namespace classes;
class Foo implements toolInterface {
    function __construct(){
        echo __CLASS__; 
    }

    public function tool(){

    }
}

I have a problem with spl_autoload_register, above example works fine, but when I try to use use classes it will have fatal error, anyone know how to solve this problem?

//fatal error
spl_autoload_register(function($class){
    require_once "{$class}.php";
});

use classes;
new Foo();

Answer 1

The ability to refer to an external fully qualified name with an alias

Note that for namespaced names (fully qualified namespace names containing namespace separator, such as Foo\Bar as opposed to global names that do not, such as FooBar), the leading backslash is unnecessary and not recommended, as import names must be fully qualified, and are not processed relative to the current namespace.

PHP: Using namespaces: Aliasing/Importing

So we need the fully qualified name

use classes\Foo;
new Foo();