如何在原型模式下创建一个私有静态变量(How to create a private static variable in prototype pattern)

 在下面的代码中，所有实例化的Page对象都从静态变量'nextId'获得它们的Id。 什么是重置nextId的最佳方法？ 我不喜欢我这样做的方式，因为它是通过实例化对象访问的。 我宁愿做一些事情： 
 
 Page.reset（）。 这怎么可能？ 
 
 https://plnkr.co/edit/heOz52QxK6CExhe8Hdfm?p=preview 
 
var Page = (function() {

var nextId = 0;

function Page(content) {
    this.id = nextId++;
    this.content = content;
}

Page.prototype.reset = function() {
    nextId = 0;
}   

Page.prototype.show = function() {
    console.log(this.content + ' is ' + this.id);
}

return Page;



}())


var a = new Page('a')
a.show() // a is 0

var b = new Page('b')
b.show() // b is 1

var c = new Page('c')
c.show() // c is 2

a.reset()

var d = new Page('d')
d.show() // d is 0

In the code below, all instaniated Page objects get their Id from the static variable 'nextId'. What is the best way to reset nextId? I don't like the way I'm doing it because it's accessed through an instantiated object. I'd rather do something like:
 
Page.reset(). How is it possible?
 
https://plnkr.co/edit/heOz52QxK6CExhe8Hdfm?p=preview
 
var Page = (function() {

var nextId = 0;

function Page(content) {
    this.id = nextId++;
    this.content = content;
}

Page.prototype.reset = function() {
    nextId = 0;
}   

Page.prototype.show = function() {
    console.log(this.content + ' is ' + this.id);
}

return Page;



}())


var a = new Page('a')
a.show() // a is 0

var b = new Page('b')
b.show() // b is 1

var c = new Page('c')
c.show() // c is 2

a.reset()

var d = new Page('d')
d.show() // d is 0

原文：https://stackoverflow.com/questions/39581592