JavaScript:获取和设置对象的嵌套属性

Question

网络和 StackOverflow 上也有关于如何在 JS 中获取和设置对象的嵌套属性/属性的问题和答案，但到目前为止没有一个适合我的问题，所以就在这里。

声明/定义对象的代码是

/**
 * a dummy class for experiments
 */

module.exports = function() {
  this.Delme = () => {
    const attrs = {
      name: '',
      age: '',
      addr: {
        street: '',
        city: '',
        pin: ''
      }
    };

    return Object.create({
      set(name, value) {
        if (attrs.hasOwnProperty(name)) {
          console.log(`setting attrs.${name} to ${value}`);
          attrs[name] = value;
          return true;
        } else {
          console.log(`Object has no property named ${name}`);
          return false;
        }
      },

      get(name) {
        if (attrs.hasOwnProperty(name)) {
          return attrs[name];
        } else if (attrs.addr.hasOwnProperty(name)) {
          return attrs.addr[name];
        } else {
          return null
        }
      }
    });
  };
};

/**
 * Based on some other posts I wrote this anyway, 
 * but I'm not sure how to use this in my object creation.
 * 
 * function() returning an 'addr' object
 */

const Address = function() {
  const _addr = {
    street: '',
    city: '',
    pin: ''
  };

  return Object.create({
    set(name, value) {

      if (_addr.hasOwnProperty(name)) {
        console.log(`setting _addr.${name} to ${value}`);
        _addr[name] = value;
        return true;
      } else {
        console.log(`Object has no property named ${name}`);
        return false;
      }

    },

    get(name) {
      return _addr[name];
    }
  });
}
// Above function is currently not used

这是我用来测试对象创建的代码

require('../lib/delme')();

const personFactory = function (target) {
    return Delme.call(target);
} ;

const george = { name: 'george' };
const person = personFactory(george);

//person.on('change', data => console.log(data));

person.set('name', 'Sam');
console.log(person.get('name'));

person.set('unknown', 'anything');
console.log(person.get('unknown'));

console.log(person.hasOwnProperty('name'));

const person9 = personFactory({name: 'Charlie', age :'27'});
console.log(person9.get('name'));
console.log(person9.set('age', '42'));
console.log(person9.get('age'));

person9.set('addr', {street:'main road', city:'somewhere', pin:'560032'});
//console.log(person9.addr.city)
console.log(person9.get('city'));

person9.set('addr[street]', '3rd Lane')
console.log(person9.get('street'));

输出是

setting attrs.name to Sam
Sam
Object has no property named unknown
null
false

setting attrs.age to 42
true
42
setting attrs.addr to [object Object]
somewhere
Object has no property named addr[street]
main road

Q.1:如何正确获取()和设置()嵌套属性。我希望能够person.get('addr.street') 和 person.set('addr.pin', '123456')。目前我只能通过在对象创建期间传递它来设置整个 addr 对象。

Q2。我怎样才能让我的类(class)发出事件，这样我就可以像 person.on('change', data => console.log(data));

这样的代码

Answer 1

我建议您使用 ES6 类语法而不是原型(prototype)并实现 set 和 get 作为方法。对于问题 2，没有简单的方法可以做到这一点。您可以使用诸如 pubsub-js 之类的库手动实现它，以在 set 和 get 方法中发出事件。