Encapsulating in JavaScript, does it exist?

Question

I have an experience with the C# programming language, but I also have to work with the JS now and it\'s rather new for me.

I have tried to develop a simple class em

Answer 1

You can use closures to encapsulate variables.

function MyObjectFactory() {
  var obj = {},
    count = 0;

  obj.getCounter = function () {
    return count;
  };

  obj.setCounter = function (val) {
    count = val;
  };

  obj.incrementCounter = function () {
    count++;
  };

  obj.decrementCount = function () {
    count--;
  };

  return obj;  
}

You can also imitate property getters and setters in generic way.

function MyOtherObjectFactory() {
  var obj = {}, props = {};

  obj.prop = function (name) {
    return props[name];
  };

  obj.setProp = function (name, val) {
    props[name] = val;
    // call other functions if you'd like
  };


  // or even better, have a single function that works getter and setter regarding the params
  obj.autoProp = function () {
    if (arguments[1]) {
      // setter
      props[arguments[0]] = arguments[1]; // do check first argument is a hashable value
    } else if (arguments[0]) {
      // make sure we have a key
      // getter
      return props[arguments[0]];
    }
  }
}

PS: Please don't set prototype directly, it breaks the prototype chain.