ConstructorFunctions.js

/*  Ok, here are my summary notes for the different ways to create multiple instances of an Object.

1. class.create
2. constructor function with 'new'
3. Object.create
4. factory function

*/

// 1. ServiceNow class.create . *** object written using Pascal notation (first letter uppercase)
var Person = Class.create();
Person.prototype = {
    initialize: function (first, last) {
        this.first = first || 'Default';
        this.last = last || 'Default';
        this.getFullName = function () {
            return this.last + ', ' + this.first;
        }
        // return this; is implied
    },

    getFormalName: function () {
        return this.last + ', ' + this.first;
    },

    type: 'Person'
};

/// how to use/
var sally = new Person('Sally', 'Smith');
sally.getFullName();
sally.getFormalName();


// 2. constructor function using 'new' keyword . *** object written using Pascal notation (first letter uppercase)
function Person(first, last) {
    this.first = first || 'Default';
    this.last = last || 'Default';
    this.getFullName = function () {
        return this.first + ' ' + this.last;
    }
    // return this; is implied
}

// how to use
var sally = new Person('Sally', 'Smith');  
sally.first;
sally.last;
sally.getFullName();


// 3. Object.create()  *** object written using Camel notation (first letter lowercase)
var person = {
    first: 'Default',
    last: 'Default',
    getFullName: function () {
        return this.first + ' ' + this.last;
    }
};

// how to use
var sally = Object.create(person);
sally.first = 'Sally';
sally.last = 'Smith';
sally.getFullName();


// 4. factory function . *** object written using Camel notation (first letter lowercase)
function person(first, last) {
    return {
        first: first || 'Default first',
        last: last || 'Default last',
        getFullName: function () {
            return this.first + ' ' + this.last;
        }
    };
}

// How used
var sally = person('Sally', 'Smith');
sally.first;
sally.last;
sally.getFullName();