zig Tryit Editor

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<h1>JavaScript Objects</h1>
<h2>The Object.defineProperty() Method</h2>

<p>JavaScript Getters and Setters are perfect for creating counters:</p>

// Define Setters and Getters
  Object.defineProperty(obj, "reset", {
    get: function () { this.counter = 0; }
  });
  Object.defineProperty(obj, "increment", {
    get: function () { this.counter++; }
  });
  Object.defineProperty(obj, "decrement", {
    get: function () { this.counter--; }
  });
  Object.defineProperty(obj, "add", {
    set: function (value) { this.counter += value; }
  });
  Object.defineProperty(obj, "subtract", {
    set: function (value) { this.counter -= value; }
  });

// Play with counter:
  obj.reset;
  obj.add = 5;
  obj.subtract = 1;
  obj.increment;
  obj.decrement;
  document.getElementById("demo").innerHTML = obj.counter;
</script>

</body>

</html>