<?php
class foo
{
public $foo = 1;
// everyone can access
private $bar = 2;
// can only be accessed by the class internally
protected $baz = 3;
// can be accessed by the class internally & any extending classes
function p1()
{
echo $this->foo . $this->bar . $this->baz;
}
}
class foo_ex extends foo
{
function p2()
{
echo $this->foo . $this->bar . $this->baz;
}
}
$a = new foo();
echo $a->p1();
// will print 123
$b = new foo_ex();
echo $b->p2();
// will print 13 + notice about unknown property foo_ex::$bar
// accessing private/protected properties directly will result is a E_ERROR (fatal error)
echo $a->foo . $a->bar . $a->baz;