多态小例子

<?php

    interface Computer {
        public function version();
        public function work();
    }

    class NoteComputer implements Computer {
        public function version(){
            echo ‘笔记本‘;
        }
        public function work(){
            echo ‘可以便携运行WIN7！！‘;
        }
    }

    class DesktopComputer implements Computer {
        public function version(){
            echo ‘台式机！‘;
        }
        public function work(){
            echo ‘在工作站运行XP!‘;
        }
    }

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

    //多态的原理就是，类都写好了~不要去修改它~只要在类外的调用参数更改
    //最后的结果也会修改，那么这个就是多态


    $notecomputer = new NoteComputer();
    $desktopcomputer = new DesktopComputer();

    $person = new Person();
    $person->_run($notecomputer); //对象引用传递，持有对方的引用
    echo ‘<br/>‘;
    $person->_run($desktopcomputer);

?>