Access control modifiers in php

There are a number of special keywords you can place before a class, a class function definition, or a class variable to alter the way PHP works with it - here's the full list, along with what each of them does:

• Public: This variable or function can be used from anywhere in the script
• Private: This variable or function can only be used by the object it is part of; it cannot be accessed elsewhere
• Protected: This variable or function can only be used by the object it is part of, or descendents of that class
• Final: This variable or function cannot be overridden in inherited classes
• Abstract: This function or class cannot be used directly - you must inherit from them first

That is just a vague description of what each of them do - to make sure you fully understand each of them, here are examples:

<?php

class Example {

    public $a = 1;

    protected $b = 2;

    private $c = 3;

    

    function show_abc()

{

        echo $this -> a ;

        echo $this -> b;

        echo $this -> c;

    }

}

$example = new Example();

echo "Publc a: {$example->a}<br/>";

//echo "Protected b: {$example->b}<br/>";

//echo "Private c: {$example->c}<br/>";

$example->show_abc();

?>