深入理解面向对象三大特性——多态

//举例：创建一个电脑的接口
interface Computer
{
    public function version();
    public function work();
}

//创建一个笔记本的子类实现接口
class Notecomputer implements Computer
{
    public function version()
    {
        echo ‘笔记本‘;
    }
    public function work()
    {
        echo ‘可以运行Win7‘;
    }
}

//创建一个台式机的子类实现接口
class Desktopcomputer implements Computer
{
    public function version()
    {
        echo ‘台式机‘;
    }
    public function work()
    {
        echo ‘可以运行XP‘;
    }
}

//创建一个人的类
class Person
{
    public function doing($type)
    {
        echo ‘这个人的‘;
        $type->version();
        $type->work();
    }
}

$notecomputer = new Notecomputer();
$desktopcomputer = new Desktopcomputer();
$demo = new Person();
$demo->doing($desktopcomputer);//输出这个人的台式机可以运行XP

abstract class Computer
{
    abstract public function version();
    abstract public function work();
}

class Notebook extends Computer
{
    public function version()
    {
        echo ‘笔记本‘;
    }
    public function work()
    {
        echo ‘在运行Win7‘;
    }
}

class Desktopcomputer extends Computer
{
    public function version()
    {
        echo ‘台式机‘;
    }
    public function work()
    {
        echo ‘在运行XP‘;
    }
}

class Person
{
    public function _run($type)
    {
        echo ‘这个人的‘;
        $type->version();
        $type->work();
    }
}

$nc = new Notebook();
$dc = new Desktopcomputer();
$p = new Person();
$p->_run($dc);