遍历ES6类的方法和属性 [英] Iterate through methods and properties of an ES6 class

问题描述

因此，随着使用JavaScript的新框架的增长，许多人都采用了ECMAScript 6 shim或TypeScript，它具有许多新功能.我的问题是这样:

So with the growth of new frameworks with JavaScript many have adopted ECMAScript 6 shim's or TypeScript, with many new features. My question is this:

如何遍历ES6类的方法/属性?

How does one iterate over the methods/properties of an ES6 class?

例如(带有对象)

var obj = {
  prop: 'this is a property',
  something: 256,
  method: function() { console.log('you have invoked a method'); }
}

for (var key in obj) {
  console.log(key);
}

// => 'prop'
// => 'something'
// => 'method'

(含课程)

class MyClass {
  constructor() {
    this.prop = 'prop';
    this.something = 256;
  }

  method() {
    console.log('you have invoked a method');
  }
}

如何列出MyClass的方法以及其属性(可选)?

How do I list the methods MyClass has, and optionally its properties as well?

推荐答案

constructor和任何已定义的方法都是该类的prototype对象的不可枚举属性.

The constructor and any defined methods are non-enumerable properties of the class's prototype object.

因此，您可以使用以下方法获取名称的数组(无需构造类的实例):

You can therefore get an array of the names (without constructing an instance of the class) with:

Object.getOwnPropertyNames(MyClass.prototype)

如果不创建实例就无法获取属性，但是这样做可以使用Object.keys函数，该函数仅返回对象的可枚举属性:

You cannot obtain the properties without creating an instance, but having done so you can use the Object.keys function which returns only the enumerable properties of an object:

Object.keys(myInstance)

AFAIK没有标准方法来同时获取原型的不可枚举属性和实例的可枚举属性.

AFAIK there's no standard way to obtain both the non-enumerable properties from the prototype and the enumerable properties of the instance together.

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