iframe-proxy | Sunbelt Computer Software

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<!DOCTYPE html>
<html lang="en">
    <meta charset="UTF-8">
    <title>Objects</title>
    <script>
        //Creating object literals
        const spaceship = {
            'Fuel Type': 'diesel', //These are object properties. Property -
             color : 'silver',   //comprises of an key:value pair
             homePlanet: 'Earth',
             'Active Duty': true,
             numCrew : 5,
             mission: 'Explore the universe'
        //Accessing properties
        console.log(spaceship.homePlanet);
        console.log(spaceship['homePlanet']);
        console.log(spaceship.color);
        console.log(spaceship['color']);
        console.log(spaceship['Fuel Type']);
        console.log(spaceship['Fuel Type']);
        console.log(spaceship['Active Duty']);
        console.log(spaceship['numCrew']);
        console.log(spaceship['!!!']);  //returns Undefined
        // Note that when accessing keys that have
        //numbers, spaces or special characters in them, you must use bracket notations only.
        //How to use the bracket notation in a function
        let returnAnyProp = (objectName, propName) => objectName[propName];
        console.log(returnAnyProp(spaceship, 'homePlanet'));
        //Property Assignment; Objects are mutable.
        spaceship.color = 'gold';  //changes the value of the color ppty.
        spaceship['Fuel Type'] = 'Vegetable Oil'; //changes the value of the 'Fuel Type' property.
        console.log(spaceship['color']);
        console.log(spaceship['Fuel Type']);
        spaceship.speed = 'Mach 5'; //creates a new key 'speed'.
        spaceship.type = 'alien'; //creates a new key 'type'
        console.log(spaceship.speed);
        console.log(spaceship.type);
        //spaceship = {type: 'Shuttle'}; //returns a TypeError for trying to assign
        //to a constant variable.
        //Delete a property
        delete spaceship.mission; //deletes the property 'mission'
        console.log(spaceship.mission) // returns 'undefined' cos the property has already been deleted.
        //Methods; When the data stored on an object is a function,
        //we call that a method. A property is what an object has, while
        // a method is what an object does. e.g .log(), .floor(), etc.
        const alienShip = {
            invade: function(){
                console.log('Hello! We have come to dominate your planet. Instead of Earth, it shall be called new Xaculon')
            alienShip.invade(); //Object methods are invoked by appending the
            //object's name with the dot operator followed by the method name
            //and parenthesis.
            //Nested Objects; this is when an object has another object as a property
            const shipSpace =  {
                telescope: {
                    yearBuilt: 2018,
                    model: '91031-XLT',
                    focalLength: 2032
                crew: {
                    captain: {
                        name: 'Sandra',
                        degree: 'Computer Engineering',
                        encourageTeam() {console.log('We got this!')}
                engine: {
                    model: 'Nimbus2000'
                nanoelectronics:{
                    computer: {
                      terabytes: 100,
                       monitors: 'HD'
                    'back-up': {
                        battery: 'Lithium',
                        terabytes: 50
                const outPut = shipSpace.nanoelectronics['back-up'].battery;
                console.log(outPut); //returns lithium.
                //Pass By Reference; Objects are passed by reference. When a variable assigned
                //to an object is passed into a function as an argument, the computer interprets
                //the parameter name as pointing to the space in memory holding that object.
                let paintIt = obj => {
                    obj.color = 'glorious gold'
                paintIt(spaceship);
                console.log(spaceship.color);
                //Looping through objects
                for (crewMember in shipSpace.crew){
                    console.log(`${crewMember}: ${shipSpace.crew[crewMember].name}`)
    </script>
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