/**
* 无法判定对象所属类型
*/
function createPerson(name, age, job) {
return {
name: name,
age: age,
job: job,
say: function () {
console.log(`my name is ${this.name},age is ${this.age},job is ${this.job}`)
}//这里不可用箭头函数，箭头函数中的this，arguments不会被绑定，会沿着父环境逐级向上寻找
}
}
var person1 = createPerson('lyf', 22, 'node');
person1.say();
/**
* 每个方法会在每个实例上创建一次，即方法不被不同实例共享
*/
function Person(name, job) {
this.name = name;
this.job = job;
this.say = function () {
console.log(`my name is ${this.name},job is ${this.job}`);
}
}
/**
* 1、创建一个新对象
* 2、将构造函数作用域赋值给新对象（即this指向新对象）
* 3、执行构造函数中代码
* 4、返回新对象
*/
/**
* var p1=new Person()
* 1、var p1={}
* 2、p1.__proto__=Person.prototype
* 3、Person.call(p1)
*/
var person = new Person('Lyf', 'node');
person.say();
console.log(person.constructor == Person)
/**
* 所有对象共同使用同一数据，当a修改后b中访问也是修改后的值
*/
function Person() {
}
Person.prototype = {
constructor: Person,
name: 'Lyf',
job: 'Node',
say: function () {
console.log(`my name is ${this.name},job is ${this.job}`)
}
}
var person = new Person();
person.say();
/**
* 完美
*/
function Person(name, job) {
this.name = name;
this.job = job;
if (typeof this.say !== 'function')//只有第一次才会创建原型方法
Person.prototype.say = function () {
console.log(`my name is ${this.name},job is ${this.job}`)
}
}
var person = new Person('Lyf', 'Node');
person.say();
