CODEWITHSUNDEEP
php
nshunz
nshunz

Reputation: 263

Why are public methods accessible at the class level

Consider this example,

class A {
        public function who() {
            echo 'The name of the class is ' . __CLASS__;
        }
    }
A::who();

Output: The name of the class is A

And this,

class A {
        public $vars=12;
    }
echo A::$vars;

Which results in the following error,

Fatal error: Uncaught Error: Access to undeclared static property: A::$var in G:\xampp\htdocs\Learn_PHP\PHP1\name_class.php:10 Stack trace: #0 {main} thrown in G:\xampp\htdocs\Learn_PHP\PHP1\name_class.php on line 10

What is happening? Why is a public method accessible via class? And why is the same not happening with a property?

Upvotes: 1

Views: 65

Answers (2)

treyBake
treyBake

Reputation: 6568

From the php.net page for Scope Resolution Operator:

The Scope Resolution Operator (also called Paamayim Nekudotayim) or in simpler terms, the double colon, is a token that allows access to static, constant, and overridden properties or methods of a class.

Your function is a method, hence the use of :: is ok. The variable however isn't static or a constant, nor is it an overridden property of a parent class. So the use of :: won't work for it.

full page from docs: https://secure.php.net/manual/en/language.oop5.paamayim-nekudotayim.php

Upvotes: 1

Samy Massoud
Samy Massoud

Reputation: 4385

To make the second example works as the first one just change it as follows 

 class A {
        public static $vars=12;
    }
    echo A::$vars;

By adding Static to the attribute because you are calling it in a static way.

Actually PHP allows calling none static methods in a static way as of first example, but not for none static variable.

According to documentation this behavior will be changed in PHP 7

Warning In PHP 7, calling non-static methods statically is deprecated, and will generate an E_DEPRECATED warning. Support for calling non-static methods statically may be removed in the future.

Please review this URL Static keyword in PHP

Upvotes: 0

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