array

What is Array?

What is Object?

What are predifined method in Array?

How to add elements?

How to delete elements?

How to replace elements?

Array destructuring

Array iteration:

For each: it executed a provided function for each element in the array. The code syntax is:

Map function: it created a new array with the results of calling a provided function on every element in the original array. Code syntax:

const numbers = [1,2,3,4,5]

const squares = numbers.map((element)=>{

return element*element

})

Filter function: It creates new array with all elements that pass the test implemented by the provided function. Code syntax:

const numbers = [1,2,3,4,5,6,7,8,9];

const evenNumbers = number.filter((element)=> {

return element%2 === 0

})

console.log(evenNumbers

4) array methods:

// push()
// adds one or more elements to the end of the array.
//returns new length of the array.

let myArray = [1,2,3,4,5];
console.log(myArray);
myArray.push(6,7,8);
myArray.push(9);
myArray.push(10);
myArray.push(11);
myArray.push(12);
console.log(myArray);

// pop()
// removes the last element of an array:

let myArray = [1,2,3,4,5,6];
let lastElement = myArray.pop();
console.log(lastElement);
console.log(myArray);

// unshift()
// adds one or more elements to the begining of an array and returns the
new length of the array.

let myArray = [1,2,3,4,5];
console.log(myArray);
myArray.unshift(9,8,7,6,5,4,3,2,1);
console.log(myArray);

// shift():
// removes the first element of an array and returns it.

let myArray = [1,2,3,4,5];
console.log(myArray);
let firstElement = myArray.shift();
console.log(firstElement);
console.log(myArray);

// slice():
// returns a new array that contain a portion of the original array. The portion is
specified by its start and end indices.

let myArray = [1,2,3,4,5,6,7,8,9];
// 0 1 2 3 4 5 6 7 8
console.log(myArray);
let slicedArray = myArray.slice(1,6);
console.log(slicedArray);
console.log(myArray);

// splice()
// removes one or more elements from an array and adds new element at a specified
index.
splice(start, delete count, element to add).

let myArray = [1,2,3,4,5];
// 0 1 2 3 4
console.log(myArray);
myArray.splice(1,0,'a','b','c','d','e','f','g');
console.log(myArray);

//sort():
the sort function by default sorts the array elements in ascending order.

const fruits = [55,43,22,77.53,77.52];
console.log(fruits);
fruits.sort();
console.log(fruits);

Destructuring:
array destructuring is a way of extracting values from an array and assigning them
to variables in a more concise way. It allows you to extract multiple values from an
array and assign them to the individual variables.

const [first,second,third,a,] = [1,2,3,4,5,6,7,8];
console.log(first);5 hmm
console.log(second);
console.log(third);
console.log(a);
console.log([first,second,third,a,])

Iteration:
array iteration is a way to transverse through an array and perform some action on
each element of the array element.
It takes a callback function as an arguement that is executed for each element.

1) forEach():
function executes a provided function once for each array element.

const numbers = [1,2,3,4,5,6,7,8,9];
console.log(numbers);
numbers.forEach((element) =>{
console.log(element);
});

2) map():
this function creates a new array with the results of calling a provided function on
every element in the original array. It returns a new array with the same length as
the original array.

const numbers = [1,2,3,4,5,6,7,8];
console.log(numbers);
const squares = numbers.map((element)=>{
return element * element
});
console.log(squares);

3) filter:
This function creates new array with all elements that pass the test implemented
by the provided function. It returns a new array with the filtered elements.

const numbers = [1,2,3,4,5,6,7,8];
const evenNumbers = numbers.filter((noName)=>{
return noName %2===0 ;
})
console.log(evenNumbers);
*/

How to remove duplicate value fro hmm Array:

For that use new set function👇

There is a spread operator(...) to convert the set object to array