SOURCE

class Phone {
    constructor (brand,price) {
        this.brand = brand
        this.price = price
    }
    call () {
        console.log('我可打电话')
    }
    
}
class smartPhone extends Phone{
    constructor (brand,price,color,size){
        super(brand,price)//super 继承父类的
        this.color = color
        this.size  = size
    }
    photo () {
        console.log('我可以拍照')
    }
    playgame () {
        console.log('我可以 玩游戏')
    }

    // 重写父类的call 方法 但只是当前的实例化是重写了 影响上级的上级 call 
    call () {
        console.log('我可以 重写')
    }

}

var smart_phone = new smartPhone('锤子','2499','balck','5.5inch')
console.log(smart_phone)
smart_phone.call()