如何设置JavaScript对象的私有成员

Question

我有一个dog类，其中包含私有成员，这些私有成员具有使用闭包访问这些成员的公共方法。

class Dog {

constructor(name,  age,  avail) {

    var _name, _age, _availability;

    _name = name;
    _age = age;
    _availability = avail;

    this.getName = function () {
        return _name;
    }

    this.getAge = function () {
        return _age;
    }

    this.getAvailability = function () {
        return _availability;
    }

}

Dogs[0] = new Dog("Macy","6 Years", true);

我希望能够更改能够更改_availability成员。 我尝试添加：

        this.setAvailbility = function (param) {
        if (param == "false") {
            _availability = false;
        } else if (param == "true") {
            _availability = true;
        }

但这没用。我该怎么做呢？

class Dog {

  constructor(name, age, avail) {

    var _name, _age, _availability;

    _name = name;
    _age = age;
    _availability = avail;

    this.getName = function() {
      return _name;
    }

    this.getAge = function() {
      return _age;
    }

    this.getAvailability = function() {
      return _availability;
    }
    this.setAvailbility = function(param) {
      if (param == "false") {
        _availability = false;
      } else if (param == "true") {
        _availability = true;
      }
    }

  }
}

var dog = new Dog("Macy", "6 Years", true);
dog.setAvailbility("false");
console.log(dog.getAvailability())

Answer 1

尝试像这样创建一个setter方法setAvailability(avail)：

class Dog {
  _name;
  _age;
  _availability;

  constructor(name, age, avail) {
    this._name = name;
    this._age = age;
    this._availability = avail;
  }
  
  getName() {
    return this._name;
  }

  getAge() {
    return this._age;
  }

  getAvailability() {
    return this._availability;
  }
  
  setAvailability(avail) {
    this._availability = avail;
  }
}

const dog = new Dog("Macy", "6 Years", true);

console.log('Name:', dog.getName());
console.log('Age:', dog.getAge());
console.log('Availability:', dog.getAvailability());

dog.setAvailability(false);

console.log('Updated availability:', dog.getAvailability());