Prototypes and Constructors

Example.js

function Animal(name) {
    this.name = name;
}

Animal.prototype.getName = function() {
    return this.name;
}

Animal.prototype.sayHi = function() {
    return "Hmmm...";
}


function Dog(name) {
    Animal.call(this, name);
}

Dog.prototype = Object.create(Animal.prototype); 

Dog.prototype.sayHi = function() {
    return Animal.prototype.sayHi.call(this) + " Woof!!!";
}

Dog.prototype.makeHappy = function() {
    return "Smile!";
}

function Cat(name) {
    Animal.call(this, name);
}
Cat.prototype = Object.create(Animal.prototype); 

Cat.prototype.makeHappy = function() {
    return "Meow!";
}
var rex = new Dog("Rex");
console.log(rex.getName());
console.log(rex.sayHi());
var leopold = new Cat("Leopold");
console.log(leopold.getName());
console.log(leopold.sayHi());