Page 235 - Beginning PHP 5.3

Chapter 8: Objects
$parentObj = new ParentClass;
$parentObj- > someMethod(); // Calls ParentClass::someMethod()
$childObj = new ChildClass;

$childObj- > someMethod(); // Calls ChildClass::someMethod()
Notice that the parent class ’ s method is called when accessed from an object of the parent class, and the
child class ’ s method is called when using an object of the child class.

The following example code shows how you can use inheritance to distinguish grapes from other fruit:
< !DOCTYPE html PUBLIC “-//W3C//DTD XHTML 1.0 Strict//EN”
“http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd” >
< html xmlns=”http://www.w3.org/1999/xhtml” xml:lang=”en” lang=”en” >
< head >
< title > Overriding Methods in the Parent Class < /title >
< link rel=”stylesheet” type=”text/css” href=”common.css” / >
< /head >
< body >
< h1 > Overriding Methods in the Parent Class < /h1 >

< ?php

class Fruit {
public function peel() {
echo “ < p > I’m peeling the fruit... < /p > ”;
}

public function slice() {
echo “ < p > I’m slicing the fruit... < /p > ”;
}

public function eat() {
echo “ < p > I’m eating the fruit. Yummy! < /p > ”;
}

public function consume() {
$this- > peel();
$this- > slice();
$this- > eat();
}
}

class Grape extends Fruit {
public function peel() {
echo “ < p > No need to peel a grape! < /p > ”;
}

public function slice() {
echo “ < p > No need to slice a grape! < /p > ”;
}
}

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