策略模式

<?php
class game {
    public function way(){
        echo "打王者 <br>";
    }
}
class sleep {
    public function way(){
        echo "睡觉去<br>";
    }
}
class student {
    public function play($obj){
     $obj->way();
    }
}
$stu=new student;
$stu->play(new game);
$stu->play(new sleep);
?>