构造函数原型内存图

GO ={NumberWindowPerson: 0x100Student: ox500stu: ox800}

function Person() {    this.name = 'why'}Person.prototype.eating = function() {    log(this.name + ' eating')}function Student() {    this.sno = 111}Student.prototype.studying = function() {     log(this.name + ' studying')}var stu = new Student()

0x600: Student.prototype.__proto__

key

value

scope-chain

GO

Prototype

0x600

代码块

...

0x300: Person.prototype.__proto__

0x400: eating

__proto__

null

函数

function() {    log(this.name + ' studying')}

constructor

ox500

studying

0x700

GEC

VO: GO       this

执行：new Student()          stu = new Student()

ox100

0x300

eating

0x400

FEC: Student AO

VO: GO+scope       this

执行：  1.构造函数St内部创建一个临时对象obj  2.obj.__proto__ = St.prototype  3.St内部this 绑定到obj  4.执行St内部代码  5.返回obj: ox800----AO出栈

ox600

0x600: Student.prototype

内存

(临时对象obj)-ox800

0x200: Person.prototype

0x500: Student

0x200

function() {    log(this.name + ' eating')}

0x400: studying

ECS

0x100: Person