__METHOD__ and __FUNCTION__

Question

I know difference between these two, and I've checked the manual.

I'm stll have some confusion. I can use __FUNCTION__ in method of class, this represents the name of this method. When I echo it, it just output the name. Here is clear.

But Why I can use __METHOD__ in a non-calss method. This also just represents the name of the normal funciton. Is the normal function is in some some container? and when echo __METHOD__ in the normal function, the container is nothing?

Code:

<?php
class dog {
    private $name = 'dog';

    public static function name() {
        echo __METHOD__;
        echo"\n";
        echo __FUNCTION__;
        echo"\n";
    }

}
function test() {
    echo __FUNCTION__;
    echo"\n";
    echo __METHOD__;
}

dog::name();
test();

output:

ei@localhost:~$ php test.php
dog::name
name
test
test

Any help will appreciated. Thanks.

Answer 1

"Method" is basically just the name for a function within a class (or class function). Therefore __METHOD__ consists of the class name and the function name called (dog::name), while __FUNCTION__ only gives you the name of the function without any reference to the class it might be in.

When __METHOD__ is called outside of a class it's the same as __FUNCTION__ because there is no class part to be used as a prefix. You can use __METHOD__ outside of a class because it's a magic constant and they're always available (at worst case they will return empty string).

http://php.net/manual/en/language.constants.predefined.php

Answer 2

Let me clarify your doubt..

• First I will explain about CLASS & OBJECT(what is the difference..)

• Then I will clarify about FUNCTION & METHOD(what is the difference..)

talking about Class :: It is a your logical implementation..

object :: It is a instance of your class (instance ~ COPY ~ clone ~ ...)

when you are using --NEW-- operator ---> you are creating an OBJECT (nothing but the COPY) OF YOUR CLASS.

CLASS =============> ~NEW~ =======> OBJECT (New Copy of your class..) similarly

FUNCTION ==========> ~NEW~ =======> METHOD (Belongs to Object not Class)

Class is the program you are writing while object is the copy of your class that is executing..

class resides in ROM(permanent) where as object resides in RAM(temporary memory area..)

& when you are declaring an function as static it belongs only to class not to object & you can call the same(static function) by using ClassName::staticFunctionName()

That is why there is no existence of STATIC_METHOD Rather STATIC_FUNCTION !!!

code example::

<?php

class Dog extends CI_Controller {

  public function __construct() {
    parent::__construct();
  }

  public function index($params = '') {
  }

  private $name = 'dog';

  public static function name() {
    echo 'Inside static function & inside class' . '<br>';
    echo __METHOD__ . '<br>';
    echo __FUNCTION__ . '<br>';
  }

  public function test2() {
    echo 'Inside NON STATIC function & inside class' . '<br>';
    echo __FUNCTION__ . '<br>';
    echo __METHOD__ . '<br>';
  }
}

function test() {
  echo 'Inside NON STATIC function & OUTSIDE class' . '<br>';
  echo __FUNCTION__ . '<br>';
  echo __METHOD__ . '<br>';
}

Dog::name();
test();
$somevar = new Dog;
$somevar->test2();

OUTPUT::

Inside static function & inside class
Dog::name               //Class::function
name
    
Inside NON STATIC function & OUTSIDE class
test
test
    
Inside NON STATIC function & inside class
test2
Dog::test2            //Object::method

IN Your case as you are using METHOD IN static context it showing the class name if the it would be a non static(Simple Function) it would show only function name only..