Basics Of JS

Variables

const accountId = 144553;
let accountEmail = "hitesh@google.com";
var accountPassword = "12345";
accountCity = "jaipur";
let accountState;

accountEmail = "hc@hc.com";
accountPassword = "21212121";
accountCity = "Benguluru";

console.log(accountId, accountCity);

console.table([accountId, accountEmail, accountPassword, accountCity, accountState]);

Datatypes

"use strcit";
// alert(3+3);
console.log(3+3);

console.log("Hiesh");

let name = "hitesh";
let age = 18;
let isLoggedIn = false;
let state;

// number => 2 to power 53;
// bigint
// string => ""
// boolean => true, false
// null => standalone value
// undefined =>
// symbol => unque
// object

console.log(typeof undefined);
console.log(typeof null);

Conversion Operations

let score = "hitesh";

console.log(typeof score);
console.log(typeof(score));

let valueInNumber = Number(score);
console.log(typeof valueInNumber);
console.log(valueInNumber);

// "33" => 33
// "33abc" => NaN
// true => 1; false => 0

let isLoggedIn = "hitesh";

let booleanIsLoggedIn = Boolean(isLoggedIn);
console.log("booleanIsLoggedIn", booleanIsLoggedIn);

// 1 => true; 0 => false
// "" => false
// "hitesh" => true

let someNumber = 33;
let stringNumber = String(someNumber);
console.log(stringNumber);
console.log(typeof stringNumber);

// *********opeations***********************

let value = 3;
let negValue = -value;
let strneg = -"value";
console.log(negValue);
console.log(strneg);


console.log(2+2);
console.log(2-2);
console.log(2*2);
console.log(2**3);
console.log(2/3);
console.log(2%3);

let str1 = "hello";
let str2 = "hitesh";

let str3 = str1 + str2;
console.log(str3);


console.log("1"+2);
console.log(1+"2");
console.log("1"+2+2);
console.log(1+2+"2");
console.log((3+4)*5%3);

console.log(+true);
console.log(+"");

let num1, num2, num3;

num1 = num2 = num3 = 2+2;

console.log(num1, num2, num3);

let ganeCounter = 100;
++ganeCounter;
console.log(ganeCounter);
// link to study
// https://tc39.es/ecma262/multipage/abstract-operations.html#sec-type-conversion

Comparison

console.log(2 > 1);
console.log(2 >= 1);
console.log(2 < 1);
console.log(2 == 1);
console.log(2 != 1);

console.log("numbers");
console.log("2" > 1);
console.log("02" > 1);

console.log("nulls")
console.log(null > 0);
console.log(null == 0);
console.log(null >= 0);

console.log("undefined")
console.log(undefined == 0);
console.log(undefined > 0);
console.log(undefined < 0);

console.log("2" === 2)

Strings

const name = "hitesh";
const repocount = 50;

console.log(name + repocount + "value");
console.log(`Hello my name is ${name} and my repo count is ${repocount}`);

const gameName = new String("hitesh-hc-com");
console.log(gameName[0]);
console.log(gameName.__proto__);
console.log(gameName.length);
console.log(gameName.toUpperCase());
console.log(gameName.charAt(2));
console.log(gameName.indexOf("t"));

const newString = gameName.substring(0, 4);
console.log(newString);

const anotherString = gameName.slice(-8, 4);
console.log(anotherString);

const newStringOne = "   hitesh   ";
console.log(newStringOne);
console.log(newStringOne.trim());

const url = "https://hitesh.com/hitesh%20choudhary";
console.log(url.replace("%20", "-"));
console.log(url.includes("sunder"));
console.log(gameName.split("-"));

Number Maths

const score = 400;
console.log(score);

const balance = new Number(100);
console.log(balance);

console.log(balance.toString().length);
console.log(balance.toFixed(1));

const otherName = 123.8966;
console.log(otherName.toPrecision(4));

const hundreds = 100000;
console.log(hundreds.toLocaleString('en-IN'));

// ++++++++++++++++++++++ Maths ++++++++++++++++
console.log(Math);
console.log(Math.abs(-4));
console.log(Math.round(4.6));
console.log(Math.ceil(4.2));
console.log(Math.floor(4.9));
console.log(Math.min(4, 3, 6, 8));
console.log(Math.max(4, 3, 6, 8));

console.log(Math.random());
console.log((Math.random()*10)+1);
console.log(Math.floor(Math.random()*10)+1);

const min = 10;
const max = 20;

console.log(Math.floor(Math.random()*(max-min + 1))+ min);

Dates

let myDate = new Date();
console.log(myDate.toString());
console.log(myDate.toDateString());
console.log(myDate.toLocaleDateString());
console.log(typeof myDate);

// let myCreatedDate = new Date("01-14-2023");
// let myCreatedDate = new Date(2023, 0, 23);
let myCreatedDate = new Date(2023, 0, 23, 5, 3);
console.log(myCreatedDate.toLocaleString);

let myTimeStmap = Date.now();

console.log(myTimeStmap);
console.log(myCreatedDate.getTime());
console.log(Math.floor(Date.now()/1000));

let newDate = new Date();
console.log(newDate);
console.log(newDate.getMonth()+1);
console.log(newDate.getDay());

// `${newDate.getDay()} and the time`

newDate.toLocaleString("default", {
    weekday: "long"
})

Datatypes Summary

// primitve

// 7 types - string, number, boolean, null, undefined, symbol, bigint

const score = 100;
const scoreValue = 100.3;

const isLoggedIn = false;
const outsideTemp = null;
let userEmail;

const id = Symbol("123");
const anotherId = Symbol("123");

console.log(id === anotherId);

const bigNumber = 234566566566n;

// reference(Non-Primitve)

// Array, Objects, funtions

const heroes = ["Shaktiman", "Naagraj", "Doga"];
let myObj = {
    name: "Hitesh",
    age: 22
};

const myFunction = function(){
    console.log("Hello World");
}

console.log(typeof anotherId);