JavaScript Array fill() Method

The JavaScript Array fill() Method fills a given range of array elements with the given value. This method is used to manipulate the existing array according to our needs.

Syntax:

arr.fill(value,start,end)

Parameters:

• Value: Value to be filled.
• Start: Start index (included) and its default value is 0.
• End: End index (excluded) and its default index is this.length.

Return value: It returns the modified array.

Example 1: In this example, we will fill an array with 0 starting from an index at 2 till the end index of 4.

JavaScript

// input array contain some elements.
let array = [1, 2, 3, 4];

// Here array.fill function fills with 0
// from position 2 till position 3.
console.log(array.fill(0, 2, 4));

Output:

Array [1, 2, 0, 0]

Example 2: In this example, we will fill the array with 9 starting from an index at 2 till the end index of the array.

JavaScript

// input array contain some elements.
let array = [1, 2, 3, 4, 5, 6];

// Here array.fill function fill with
// 9 from position 2 till end.
console.log(array.fill(9, 2));

Output:

Array [1, 2, 9, 9, 9, 9]

Example 3: In this example, we will fill the array completely with 6. This is done by not giving the start and end index to the fill method.

JavaScript

// input array contain some elements.
let array = [1, 2, 3, 4];

// Here array.fill function fill with
// 6 from position 0 till end.
console.log(array.fill(6));

Output:

Array [6, 6, 6, 6]

We have a complete list of Javascript Array methods, to check those please go through this Javascript Array Complete reference article.

Supported Browsers:The browsers supported by JavaScript Array join() method are listed below:

• Google Chrome 1.0 and above
• Microsoft Edge 12 and above
• Mozilla Firefox 1.0
• Safari 1 and above
• Opera 4 and above

We have a Cheat Sheet on Javascript where we covered all the important topics of Javascript to check those please go through Javascript Cheat Sheet-A Basic guide to JavaScript.