Example PHP Abstract Class

gistfile1.php

<?php

//Define a new Abstract class for all 'shapes' to extend
abstract class Shape {

    //Define the methods required for classes to extend
    //the abstract class
    abstract protected function getColor();

    abstract protected function setColor($color);    

    //Common function available to all classes extending the Shape class
    public function describe() {
        return sprintf("I'm an %s %s\n", $this->getColor(), get_class($this));
    }   

}

//Define a new 'Triangle' class that extends the
//'Shape' abstract class
class Triangle extends Shape {

    private $color = null;

    //Define the required methods defined in the abstract
    //class 'Shape'
    public function getColor() {
        return $this->color;
    }   

    //Note that the method signature matches the abstract
    // class with only one parameter
    public function setColor($color) {
        $this->color = $color;
    }   
}

//Instantiate the Triange class
$triangle = new Triangle();

//Set the color
$triangle->setColor('Orange');

//Print out the value of the describe common method
//provided by the abstract class
//Will print out out "I'm an Orange Triange"
print $triangle->describe();

radius=$r; } public function total(){ retutn 3.14*$this->$r*$this->$r; } } $obj = new circle(); $obj->total(); ?>

radius=$r; } public function total(){ retutn 3.14*$this->$r*$this->$r; } } $obj = new circle(); echo $obj->total(); ?>

radius=$r; } public function total(){ return 3.14*$this->radius * $this->radius; } } $obj = new circle(); echo $obj->total(); ?>