有私人财产ES6类中的方法

问题描述

我只是试图ES6，并想要重写一部分的代码写在常规javascript到ES6。现在，我试图在ES6类中重写私有属性和方法时卡住了。看起来ES6中的类没有显式地提供任何东西来拥有私有数据或方法。

此外，我查看了此主题：，发现我们可以使用存储私人数据。这是一种奇怪，但它仍然可以是一个工作。我设法使用它的私人数据。

但是私人方法呢？在ES6类中使用私有方法（或甚至受保护的方法）的推荐方法是什么？

如果任何人都可以向我展示干净方式，使用ES6类和私有方法重写这部分代码，我将非常感激。

谢谢。

这是原来的老的JavaScript代码：

  function Deferred {
 
 //私人数据
 var isPending; 
 var handlers = {
 resolve：[]，
 reject：[]，
 notify：[] 
}; 
 
 //初始化实例
 init（）; 
 
 function init（）{
 isPending = true; 
 this.promise = new Promise（this）; 
} 
 
 //公共方法
 this.resolve = function（value）{
 trigger（'resolve'，value）; 
}; 
 
 this.reject = function（reason）{
 trigger（'reject'，reason）; 
}; 
 
 this.notify = function（value）{
 trigger（'notify'，value）; 
}; 
 
 this.on = function（event，handler）{
 ... 
}; 
 
 //私有方法
函数触发器（事件，参数）{
 ... 
} 
} 
  
 
 
解决方案
正确。  class 语法用于带有原型方法的普通类。如果你想要私有变量，你一直把它们放在构造函数中：
  class Deferred {
 constructor 
 //初始化私有数据
 var isPending = true; 
 var handlers = {
 resolve：[]，
 reject：[]，
 notify：[] 
}; 
 
 //私有方法
函数触发器（事件，参数）{
 ... 
} 
 
 //初始化公共属性
 this.promise = new Promise（this）; 
 
 //并创建特权方法
 this.resolve = trigger.bind（null，'resolve'）; 
 this.reject = trigger.bind（null，'reject'）; 
 this.notify = trigger.bind（null，'notify'）; 
 
 this.on = function（event，handler）{
 ... 
}; 
} 
} 
  
 
I'm just trying out ES6 and want to rewrite a part of code written in regular javascript to ES6. And now, I'm stuck while trying to re-write the private properties and methods in ES6 classes. It seems like classes in ES6 doesn't explicitly provide anything to have private data or methods. 
Also, I checked this thread: Private properties in JavaScript ES6 classes and found out that we could use WeakMap to store private data. Which is sort of weird but still it can be a work around. And I did manage to use it for private data. 
But what about private methods? What is the recommended way to have private methods (or even protected methods) in ES6 classes? 
I would appreciate if anyone can show me a clean way to rewrite this part of code using ES6 class along with the private methods. 
Thanks. 
Here's the plain old javascript code: 
function Deferred() {

    // Private data
    var isPending;
    var handlers = {
        resolve: [],
        reject: [],
        notify: []
    };

    // Initialize the instance
    init();

    function init() {
        isPending = true;
        this.promise = new Promise(this);
    }

    // Public methods
    this.resolve = function(value) {
        trigger('resolve', value);
    };

    this.reject = function(reason) {
        trigger('reject', reason);
    };

    this.notify = function(value) {
        trigger('notify', value);
    };

    this.on = function(event, handler) {
        ...
    };

    // Private method
    function trigger (event, params) {
        ...
    }
}
 解决方案 
Correct. The class syntax is for normal classes with prototype methods. If you want private variables, you put them in the constructor as always:
class Deferred {
    constructor() {
        // initialise private data
        var isPending = true;
        var handlers = {
            resolve: [],
            reject: [],
            notify: []
        };

        // Private method
        function trigger(event, params) {
            ...
        }

        // initialise public properties
        this.promise = new Promise(this);

        // and create privileged methods
        this.resolve = trigger.bind(null, 'resolve');
        this.reject = trigger.bind(null, 'reject');
        this.notify = trigger.bind(null, 'notify');

        this.on = function(event, handler) {
            …
        };
    }
}
                        
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