class Car extends Vehicle{ public $gas; function __construct() { parent::__construct("car",4); $this->gas = 100; } function drive(){ parent::drive(); $this->gas-= 5; echo "Now I have $this->gas percent of gas left.<br>";} } $bike = new Bicycle("bell"); echo $bike->drive("bell"); //prints 'Riding a bike with 2 wheels' echo '<br>'; $car = new Car(); echo $car->drive();//prints 'Driving a car with 4 wheels' ?> </p> <?php /* * $_SESSION $_POST $_GET
<h2>Inheritance</h2> <?php $square = new Square(); if (property_exists($square, "hasSides")) { echo "I have sides"; } ?> <h2>Overriding Parent Methods</h2> <?php $vehicle = new Vehicle(); echo $vehicle->honk() . "<br/>"; $bicycle = new Bicycle(); echo $bicycle->honk() . "<br/>"; echo $bicycle->drive() . "<br/>"; ?> <h2>Using <code>const</code></h2> <?php // :: => scope resolution operator if (Immortal::alive) { echo "I live forever!"; } ?> <h2><code>static</code> Keyword</h2> <?php echo Person::greet() . "<br/>"; echo Person::$shout . "<br/>"; ?> </body>