SIGMA WEB DEV JAVASCRIPT CLASS NOTES:

 

JavaScript Variables, Data Types & Objects | Sigma Web Development Course    - Tutorial  #55

 

console.log("Shivam");

console.log("hey this is tutorial 55");

let a = 6;// data type number ...

let b = 5;// data type number ...

let c = "Harry"; // data type "string" = collection of characters ...

// console.log(a + b + 8);

// // using typeof operator

// console.log(typeof a,typeof b,typeof c);

let _a = "Shubham"; // chalega

// var 55a = "Rohan"; // nahi chalega

// const a1 = 6; redefining const is not allowed

// a1 = a1 + 2;

// its not allowed

{

    let a = 66;

    console.log(a);

}

console.log(a);

let x = "Harry bhai";

let y = 3.33;

let z = 22;

const p = true;

let q = undefined;

let r = null;

console.log(x,y,z,p,q,r);

console.log(typeof x,typeof y,typeof z,typeof p,typeof q,typeof r);

// console.log(typeof null);  // it prints "object" but correct one is "null"  // its an INTERVIEW QUESTION ...

// ?? Wait typeof "object" = null -- because in past developer made a mistake that they write "object" = null by mistake but today we cannot change because so much old code is relia on that wrong code so we cannot change it...

// object = bohat sari chije ek entity ke bare me ...

let o = {

    name: "Harry",

    "job code": 5600,

    "is_handsome":true,

}

// console.log(o);

o.salary = "100crore";

// console.log(o);

o.salary = "500crore";

console.log(o);

// Chapter - 1 : practice set  

//Q-1.create a variable of type string and try to add a number to it

var s = "string";

console.log(s);

var n = 12;

console.log(n);

var ns = n+s;

console.log(ns);

//Q-2.use type operator to find the datatype of the string in last question

var s = "string";

console.log(s);

var n = 12;

console.log(n);

var ns = n+s;

console.log(ns);

console.log(typeof ns);

//Q-3.create a constant obj in javascript can you change it to hold a number later?

const obj = {

    key : "value",

}

obj.newkey = "newvalue";

console.log(obj);

//Q-4.try to add a new key to the const obj in problem 3 were you able to do it?

const obj = {

    key : "value",

}

obj.newkey = 11;

console.log(obj);

//Q-5.write a js program to create a word-meaning dictionary of 5 word

const o = {

    Abate : "to reduce in intensity or amount to lessen",

    Benevolent  : "showing kindness or goodwill; charitable",

    Concur : " to agree with someone or something",

    Diligent  : "hardworking and careful in one work or duties",

    Eloquent  : "fluent or persuasive in speaking or writing",

  }

  // console.log(o.Abate)

JavaScript Conditionals:if,else if,else ladder|Sigma - Tutorial #56

console.log("Shivam");

let age = 0;

let grace = 1;

age += grace;

console.log(age);

console.log(age + grace);

console.log(age - grace);

console.log(age * grace);

console.log(age / grace);

console.log(age ** grace); // exponentiation operator

console.log(age % grace); // modulus operator

// if else if else Ladder ......

if (age == 18) {

  console.log("You can drive");

} // if block

else if (age == 0) {

  console.log("Are you Kidding?");

} else if (age == 1) {

  console.log("Are you again Kidding?");

} else {

  console.log("you cannot drive");

} // else block

// NODE JS "REPEL" = Read Evalute Print Loop ...

// COMMENT***

/*I

am

multiline

comment

*/

// I am Comment

a = 6;

b = 8;

c = a > b ? a - b : b - a;

/*

translates to:

if(a>b){

    let c = a - b;

}

else{

    let c = b - a;

}

*/

// Chapter - 2 : Practice set

// Q-1: Use logical operator to find whether the age of a person is lies between 10 and 20 ...

let age = 15; // Replace this with the desired age

if (age >= 10 && age <= 20) {

  console.log("The age is between 10 and 20.");

} else {

  console.log("The age is not between 10 and 20.");

}

// Q-2: Demonstrate the use of switch case statements in javascript ...

//  not so much important ...

// Q-3: write a javascript program to find whether a number is divisible by 2 and 3 ...

var number = 18;

if (number % 2 === 0 && number % 3 === 0) {

  console.log("The number is divisible by both 2 and 3.");

} else {

  console.log("The number is not divisible by both 2 and 3.");

}

// Q-4: Write a java script program to find whether a number is divisible by either 2 or 3 ...

var number = 18;

if (number % 2 === 0 || number % 3 === 0) {

  console.log("The number is divisible by both 2 and 3.");

} else {

  console.log("The number is not divisible by both 2 and 3.");

}

// Q-5: Print "You can Drive" or "You cannot Drive" based on age being greater than 18 using ternary operator ...

var age = 19;

if (age >= 18) {

  console.log("You can Drive");

} else {

  console.log("You cannot Drive");

}