繼承:子類繼承父類或者基類,比如魅族手機、小米手機、華爲手機是子類,手機是基類。
class Phone {
public $price = 3699;//手機的起始價格
public function price(){
$this->price += 20;
return $this->price;
}
}
//魅族類price方法覆蓋基類,並把價格降300
class Meizu {
public function price(){
$this->price = parent::price() - 300;//parent::方法名()調用基類price方法
return $this->price;
}
}
$phone = new Meizu();
$phone->price();//調用price方法
echo $phone->price;//取price值