使用Object.create实现原型继承

function Base() {}

Base.prototype.say=function(){

    console.log("base say")

}

function Derived() {}

Derived.prototype = Object.create(Base.prototype);

Derived.prototype.derivedSay=function(){

    

}
const obj = new Derived();

console.log("obj",obj)

obj.say()

使用Object.setPrototypeOf实现原型继承

function Base() {}

Base.prototype.say=function(){

    

}

function Derived() {}

Derived.prototype.derivedSay=function(){

    

}

// 将 `Derived.prototype` 的 `[[Prototype]]`

// 设置为 `Base.prototype`

Object.setPrototypeOf(Derived.prototype, Base.prototype);



const obj = new Derived();

对比&&总结

Object.create实现属性继承时候，重新为 prototype 属性赋值，同时删除原型对象的constructor属性
所以需要从新更新原型对象的构造函数指向

Derived.prototype.constructor=Derived;