PHP method_exists not working on class children?

Question

class parent{
   function run($methodname) {
      echo method_exists(__CLASS__, $methodname);      
   }
}

class child extends parent {
   function order(){
      echo 'hello';
   }
}

$test = new child();
$test->run('order'); //false

The method_exists cannot find the method order in child class.

How to make it work?

Answer 1

__CLASS__ is bound to the class it's used in, not to inheriting classes. You can solve this by using $this as the object reference.

Also see http://www.php.net/manual/en/language.oop5.late-static-bindings.php.