以下是迄今为止我最喜欢的关于javascript中的私有/公共方法/成员和实例化:

这是文章:http://www.sefol.com/?p=1090

下面是一个例子:

var Person = (function () {

    //Immediately returns an anonymous function which builds our modules 
    return function (name, location) {

        alert("createPerson called with " + name);

        var localPrivateVar = name;

        var localPublicVar = "A public variable";

        var localPublicFunction = function () {
            alert("PUBLIC Func called, private var is :" + localPrivateVar)
        };

        var localPrivateFunction = function () {
            alert("PRIVATE Func called ")
        };

        var setName = function (name) {

            localPrivateVar = name;

        }

        return {

            publicVar: localPublicVar,

            location: location,

            publicFunction: localPublicFunction,

            setName: setName

        }

    }
})();


//Request a Person instance - should print "createPerson called with ben"
var x = Person("ben", "germany");

//Request a Person instance - should print "createPerson called with candide"
var y = Person("candide", "belgium");

//Prints "ben"
x.publicFunction();

//Prints "candide"
y.publicFunction();

//Now call a public function which sets the value of a private variable in the x instance
x.setName("Ben 2");

//Shouldn't have changed this : prints "candide"
y.publicFunction();

//Should have changed this : prints "Ben 2"
x.publicFunction();

JSFiddle: http://jsfiddle.net/northkildonan/kopj3dt3/1/

既然每个人都在这里张贴自己的代码，我也要这样做…

我喜欢Crockford，因为他在Javascript中引入了真正的面向对象模式。但他也产生了一个新的误解，那个“那个”。

那么他为什么要用"that = this"呢?这和私人活动完全没有关系。它与内部函数有关!

因为根据Crockford的说法，这是有bug的代码:

Function Foo( ) {
    this.bar = 0; 
    var foobar=function( ) {
        alert(this.bar);
    }
} 

所以他建议这样做:

Function Foo( ) {
    this.bar = 0;
    that = this; 
    var foobar=function( ) {
        alert(that.bar);
    }
}

就像我说的，我很确定Crockford对这个和这个的解释是错误的(但他的代码肯定是正确的)。或者他只是在愚弄Javascript世界，知道谁在复制他的代码?我不知道……我不是浏览器极客

EDIT

啊，这就是问题所在:'var that = this;'在JavaScript中是什么意思?

所以Crockie的解释是错误的....但他的代码是正确的，所以他还是个好人。:))

Class({  
    Namespace:ABC,  
    Name:"ClassL2",  
    Bases:[ABC.ClassTop],  
    Private:{  
        m_var:2  
    },  
    Protected:{  
        proval:2,  
        fight:Property(function(){  
            this.m_var--;  
            console.log("ClassL2::fight (m_var)" +this.m_var);  
        },[Property.Type.Virtual])  
    },  
    Public:{  
        Fight:function(){  
            console.log("ClassL2::Fight (m_var)"+this.m_var);  
            this.fight();  
        }  
    }  
});  

https://github.com/nooning/JSClass

我更喜欢将私有数据存储在关联的WeakMap中。这允许你将你的公共方法保留在原型上。对于大量的对象，这似乎是处理这个问题的最有效的方法。

const data = new WeakMap();

function Foo(value) {
    data.set(this, {value});
}

// public method accessing private value
Foo.prototype.accessValue = function() {
    return data.get(this).value;
}

// private 'method' accessing private value
function accessValue(foo) {
    return data.get(foo).value;
}

export {Foo};

一个丑陋但有效的解决方案:

function Class(cb) { const self = {}; const constructor = (fn) => { func = fn; }; const addPrivate = (fnName, obj) => { self[fnName] = obj; } const addPublic = (fnName, obj) => { this[fnName] = obj; self[fnName] = obj; func.prototype[fnName] = obj; } cb(constructor, addPrivate, addPublic, self); return func; } const test = new Class((constructor, private, public, self) => { constructor(function (test) { console.log(test) }); public('test', 'yay'); private('qwe', 'nay'); private('no', () => { return 'hello' }) public('asd', () => { return 'this is public' }) public('hello', () => { return self.qwe + self.no() + self.asd() }) }) const asd = new test('qweqwe'); console.log(asd.hello());

你可以这样做，但缺点是它不能成为原型的一部分:

function Restaurant() {
    var myPrivateVar;

    var private_stuff = function() {  // Only visible inside Restaurant()
        myPrivateVar = "I can set this here!";
    }

    this.use_restroom = function() {  // use_restroom is visible to all
        private_stuff();
    }

    this.buy_food = function() {   // buy_food is visible to all
        private_stuff();
    }
}