1.首选写几个函数
// 构造函数function Person(name, age, job) { this.name = name this.age = age this.job = job this.sayName = function () { alert(this.name) }}console.log(Person)var person1 = new Person('zhaojie', 55, 'leader');var person2 = new Person('zhou', 20, 'player');console.log(person1)console.log(person2)console.log(person1.constructor == Person);console.log(person2.constructor == Person);// 原型对象function Person() { Person.prototype.name = 'zhouyi' Person.prototype.age = '26' Person.prototype.job = 'engineer' Person.prototype.sayName = function () { alert(this.name) }}let person6=new Person(); person6.sayName()let person7=new Person(); person7.sayName()console.log(person6.sayName == person7.sayName)console.log(Person.prototype.constructor == Person)2.实例的_proto_属性指向原型对象原型对象的_proto属性指向原型对象 构成原型链原型对象的constructor属性指向构造函数构造函数的prototype属性指向原型对象构造函数通过new实例化实例
来源：https://www.cnblogs.com/zhouyideboke/p/9285345.html