object-creation.js

/****************************************
Creating Objects

1. Object literals
2. Object.create() with descriptors
3. function + new
4. factory function with closures
5. JS Class

****************************************/
let log = console.log;


// 1. Object literals ////////////////////////////////////
let obj1 = {
    prop1: 'value1',
    prop2: 'value2',
    prop3: function(){
        console.log(this.prop1);
    }
}
log(1, obj1);
obj1.prop3();
log('------------------------------')


// 2. Object.create ////////////////////////////////////
let proto = {
    prop3: function(){
        console.log(this.prop1);
    }
}
let obj2 = Object.create({}, {
    prop1: {
        writable: true,
        enumerable: true,
        configurable: true,
        value: 'value1'
    },
    prop2: {
        writable: true,
        enumerable: false,
        configurable: true,
        value: 'value2'
    }
});
obj2.prop3 = function(){
    console.log(this.prop1);
}
log(2, obj2);
obj2.prop3();
log('------------------------------')


// 3. new + function ////////////////////////////////////
let Obj = function(v1, v2){
    this.prop1 = v1;
    this.prop2 = v2;
    this.prop3 = function(){
        console.log( this.prop1 );
    }
}
let obj3 = new Obj('value1', 'value2');
log(3, obj3);
obj3.prop3();
log('------------------------------')


// 4. factory function with closures
let ObjFF = function(v1, v2){
    let _prop1 = v1;
    let _prop2 = v2;
    return {
        prop1: _prop1,
        prop2: _prop2,
        prop3: function(){
            console.log(_prop1);
        }
    }
}
let obj4 = ObjFF('value1', 'value2');
log(4, obj4);
obj4.prop3();
log('------------------------------')


// 5. JS Class
class ObjC{
    constructor(v1, v2){
        this.prop1 = v1;
        this.prop2 = v2;
    }
    prop3() {
        console.log( this.prop1 );
    }
}
let obj5 = new ObjC('value1', 'value2');
log(5, obj5);
obj5.prop3();