Q225: Can I add getters and setters using defineProperty method - JavaScript Internals (521 Qs)

Yes, You can use the Object.defineProperty() method to add Getters and Setters. For example, the below counter object uses increment, decrement, add and subtract properties,

javascript

  var obj = { counter: 0 };

  // Define getters
  Object.defineProperty(obj, "increment", {
    get: function () {
      this.counter++;
      return this.counter;
    },
  });
  Object.defineProperty(obj, "decrement", {
    get: function () {
      this.counter--;
      return this.counter;
    },
  });

  // Define setters
  Object.defineProperty(obj, "add", {
    set: function (value) {
      this.counter += value;
    },
  });
  Object.defineProperty(obj, "subtract", {
    set: function (value) {
      this.counter -= value;
    },
  });

  obj.add = 10;
  obj.subtract = 5;
  console.log(obj.increment); //6
  console.log(obj.decrement); //5