Array Operation with Javascript

In this article, we will be discussing the various functionalities offered by Javascript for Arrays. We will be starting with the basic Javascript functionalities along with some new features added in ES6.
So it’s almost summer and I guess fruits gonna be the best array name to start our experiments.

Note: Writing this article to serve the purpose of quick revision through most of the array features offered by Javascript.

Array Declaration

let fruits = [“mango”,”apple”];
console.log(fruits);
//Output :[ ‘mango’, ‘apple’ ]

Array length

let fruits = [“mango”,”apple”];
console.log(fruits.length);
//Output : 2 

Adding element at the end of the array

fruits.push(“watermelon”);
console.log(fruits);
//Output : [ ‘mango’, ‘apple’, ‘watermelon’ ]

Deleting element from the end of the array

fruits.pop();
console.log(fruits);
//Output: [ ‘mango’, ‘apple’ ]

Deleting element from the start of the array

fruits.shift();
console.log(fruits);
//Output: [ ‘apple’ ]

Adding element at the start of the array

fruits.unshift(“banana”);
console.log(fruits);
//Output: [ ‘banana’, ‘apple’ ]

Slicing Array into parts

numbers = [12,31,23,76,3,9,45,2];
let fristTwo = numbers.slice(0,2);
console.log(fristTwo)
//Output: [12, 31]

Sort numeric array

numbers = [12,31,23,76,3,9,45,2];
console.log(“Original Array: “ + numbers)
let numberSort = numbers.sort((a,b) => { return a-b })
// return b-a for decending order
console.log(“Sorted Array: “ + numberSort)
/*Output:
Original Array: 12,31,23,76,3,9,45,2
Sorted Array: 2,3,9,12,23,31,45,76 */

Sort array alphabetically

fruits = [“mango”,”apple”,”watermelon”,”banana”]
let fruitSort = fruits.sort()
console.log(fruitSort)
//Output: [ 'apple', 'banana', 'mango', 'watermelon' ]

Reversing Array

fruits = [“mango”,”apple”,”watermelon”,”banana”]
fruits.reverse()
console.log(fruits);
//Output: [ 'banana', 'watermelon', 'apple', 'mango' ]

Array Iteration

Looping through array using forEach

fruits = [“mango”,”apple”,”watermelon”,”banana”]
fruits.forEach((fruit,index) => {
console.log(`${fruit} is at index ${index} in the array`)
})
/*Output:
mango is at index 0 in the array
apple is at index 1 in the array
watermelon is at index 2 in the array
banana is at index 3 in the array */

Filtering array according to the requirement

let numbers = [12,31,23,76,3,9,45,2];
let evennumber = numbers.filter(number => number%2==0)
console.log(‘Original Array: ‘ + numbers)
console.log(‘Filtered Array: ‘ + evennumber)
/*Output:
Original Array: 12,31,23,76,3,9,45,2
Filtered Array: 12,76,2 */

Modifying array according to requirement

let numbers = [12,31,23,76,3,9,45,2];
let timeTwo = numbers.map(number => number*2)
console.log(‘Original Array: ‘ + numbers)
console.log(‘Modified Array: ‘ + timeTwo)
/*Output:
Original Array: 12,31,23,76,3,9,45,2
Modified Array: 24,62,46,152,6,18,90,4 */

Array to String

fruits = [ "apple", "banana", "mango", "watermelon" ]
console.log(fruits.toString)
//Output: apple,banana,mango,watermelon

Concatenation of two array

let fruits = [“apple”,”mango”,”banana”]
let veggies = [“potato”,”onion”,”spinach”]
let food = fruits.concat(veggies);
console.log(food)
//Output: [ 'apple', 'mango', 'banana', 'potato', 'onion', 'spinach' ]

To be updated soon with few more functionalities of Array