Question

Is it okay to add properties to an object at runtime? It seems to run okay but are there any issues I should be aware of?

I’m using a 3rd party javascript API which has an object class, which I’ve instantiated and added my own property to after instantiation, like the code below:

For example can I do this:

var Car = function (id, type) {
    this.id = id;
    this.type = type;
};

var myCar = new Car(1,"Nissan");

// CAN I DO THIS: (needsWork not a property of object Car)
myCar.needsWork = true;

Answer 1

Yea, this is called object augmentation. It is a key feature in JavaScript.