Everything you need to know about JavaScript Array

Samiul Islam — Thu, 16 Sep 2021 14:06:35 +0000

In this article, I will discuss everything you need to know about Array in JavaScript. So, Let’s get started 😐

1. Create an Array

// Create an array
const colors = ['black', 'white', 'green', 'blue'];

2. Getting length of an Array

// Getting length of an Array 
const arrLength = colors.length;
console.log('The length of the array is = ', arrLength);
// Expected output: The length of the array is =  4

3. Getting element by index position

// Getting element by index position
const getValueByIndex = colors[0];
console.log('Index of first element is = ', getValueByIndex);
//Expected output: Index of first element is =  black

4. Array indexOf() method => Used to get index of any single element

// Array indexOf() method => Used to get index of any single element
const getIndexByValue = colors.indexOf('white');
console.log('The index of the element is = ', getIndexByValue);
// Expected output: The index of the element is =  1

5. Array push() method => Used to add element at end of an Array

// Array push() method => Used to add element at end of an Array
console.log('Previous array', colors);
colors.push('Orange'); // Added 13 at the end of previous array colors
console.log('Array after pushing a value ', colors);
/* Expected Output: 
Previous array [ 'black', 'white', 'green', 'blue' ]
Array after pushing a element  [ 'black', 'white', 'green', 'blue', 'Orange' ] */

6. Array pop() method => Used to remove last element from an Array

// Array pop() method => Used to remove last element from an Array
console.log('Array before pop', colors);
colors.pop(); // Removed last element of the array colors
console.log('Array after pop', colors);
/*Expected OutPut: 
Array before pop [ 'black', 'white', 'green', 'blue', 'Orange' ]
Array after pop [ 'black', 'white', 'green', 'blue' ] */

7. Array includes() method => Used to check whether an array includes a certain element inside its entries, and return true or false.

// Array includes() method => Used to check whether an array includes a certain element inside its entries, and return true or false.
const isSkyBlueAdded = colors.includes('sky-blue');
console.log(isSkyBlueAdded);
// Expected Output: false

Thanks for your patience 😎
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