Basics of JavaScript

How to print a simple statement

console.log('Hello World.'); //How to print "Hello World"

Hello World.

How to declare variables in JavaScript

You can declare a variable using the two statements below
NOTE: JavaScript is case sensitive like Java

let newVariable;
myVariable = 'Shraddha';

You can also declare a variable with one line of code

let newVariable = 'Shraddha';

How to declare different types of variables

A string variable is used for a value, like a word
- Make sure to include single quotation marks
A number variable can be used by simply declaring the variable equal to the value of the number
Booleans, like in java, can be used by letting the variable equal either true or false
An Array can be used to store multiple values in one
You can store an object as a variable in JavaScript, which is a little different from in Java

let newString = 'Shraddha'; //String variable
let newNumber = 5; //Number variable
let newBoolean = true; //Boolean variable
let newArray = [1, 'Shraddha'. 5]; //Array variable
let newObject = document.querySelector('a1'); //Object as a variable

iJavaScript $$.async()

This is used to request synchronous code. This will then evaluate the code and be ready to get more requests

$$.async();

console.log("Hello, World!");

setTimeout($$.done, 1000)

Hello, World!

You can aso add a timer to print a line of code after a while

$$.async();

console.log("Hello, World!"); //How to print "Hello World" wih JavaScript

var action = {
    $$: $$,
    console: console,
};

setTimeout(function() {
    $$.clear(0);    // clear output cell
    action.$$.sendResult("Goodbye!");
}, 5000);  // 5 second timer

'Goodbye!'

Building an Array with my Scrumtean

// define a student Array of Person(s)
var students = [ 
    new Person("Shraddha", "ftc13184-SK", 2023),
    new Person("Pravavi", "PranaviInukurti", 2023),
    new Person("Madhumita", "mnarayan", 2023),
    new Person("Meena", "MAnn, 2023),
    new Person("Rebecca", "Rebecca-123", 2023)
];

// define a classroom and build Classroom objects and json
function Classroom(teacher, students){ // 1 teacher, many student
    // start Classroom with Teacher
    teacher.setRole("Teacher");
    this.teacher = teacher;
    this.classroom = [teacher];
    // add each Student to Classroom
    this.students = students;
    this.students.forEach(student => { student.setRole("Student"); this.classroom.push(student); });
    // build json/string format of Classroom
    this.json = [];
    this.classroom.forEach(person => this.json.push(person.toJSON()));
}

// make a CompSci classroom from formerly defined teacher and students
compsci = new Classroom(teacher, students);

// output of Objects and JSON in CompSci classroom
logItType(compsci.classroom);  // constructed classroom object
logItType(compsci.classroom[0].name);  // abstract 1st objects name
logItType(compsci.json[0]);  // show json conversion of 1st object to string
logItType(JSON.parse(compsci.json[0]));  // show JSON.parse inverse of JSON.stringify
object ; [ Person { name: 'Mr M', ghID: 'jm1021', classOf: 1977, role: 'Teacher' },
  Person {
    name: 'Anthony',
    ghID: 'tonyhieu',
    classOf: 2022,
    role: 'Student' },
  Person { name: 'Bria', ghID: 'B-G101', classOf: 2023, role: 'Student' },
  Person { name: 'Allie', ghID: 'xiaoa0', classOf: 2023, role: 'Student' },
  Person {
    name: 'Tigran',
    ghID: 'Tigran7',
    classOf: 2023,
    role: 'Student' },
  Person {
    name: 'Rebecca',
    ghID: 'Rebecca-123',
    classOf: 2023,
    role: 'Student' } ]
string ; Mr M
string ; {"name":"Mr M","ghID":"jm1021","classOf":1977,"role":"Teacher"}
object ; { name: 'Mr M', ghID: 'jm1021', classOf: 1977, role: 'Teacher' }