JavaScript 类与继承

原型链继承

// 本质 => Child.prototype.__proto__ = Parent.prototype
function inherit(Child, Parent) {
    function F(){};
    F.prototype = Parent.prototype;
    Child.prototype = new F();
    Child.prototype.constructor = Child; //修复constructor
}

function Animal(legsNumber){
    this.legsNumber = legsNumber;
}

function Dog(){
    this.name = name;
    Animal.call(this, 4); // **关键代码**
}

inherit(Dog, Animal); // **关键代码**

Dog.prototype.kind = '狗'
Dog.prototype.say = function(){
  console.log(`汪汪汪~ 我是${this.name}，我有${this.legsNumber}条腿。`)
}

const d1 = new Dog('啸天') // Dog 函数就是一个类
console.dir(d1)

类继承

class Animal{
    constructor(legsNumber){
        this.legsNumber = legsNumber;
    }
    run(){}
}

class Dog extends Animal{
    constructor(name){
        super(4);
        this.name = name;
    }
    say(){
        console.log(`汪汪汪~ 我是${this.name}，我有${this.legsNumber}条腿。`)
    }
}