How to Swap Two Array Elements in JavaScript: A Step-by-Step Guide

Swapping two elements in an array may seem challenging, but it’s actually quite simple in JavaScript. In this article, we will explore two methods to accomplish this task.

Method 1: Using a Temporary Variable

Let’s assume we have an array a with five elements: ['a', 'b', 'c', 'e', 'd']. Our goal is to swap the element at index 4 ('d') with the element at index 3 ('e').

To achieve this, we can follow these steps:

Create a temporary variable, tmp, and assign it the value of the element at index 4: const tmp = a[4].
Replace the element at index 4 with the value of the element at index 3: a[4] = a[3].
Assign the temporary variable (tmp) to the element at index 3: a[3] = tmp.

Here’s the complete code:

const a = ['a', 'b', 'c', 'e', 'd'];
const tmp = a[4];
a[4] = a[3];
a[3] = tmp;

After executing these steps, the array a will be updated with the swapped elements:

1	a // ['a', 'b', 'c', 'd', 'e']

Method 2: Using Array Destructuring

An alternative method that doesn’t require declaring a temporary variable is using array destructuring. Here’s how you can achieve this:

1 2	const a = ['a', 'b', 'c', 'e', 'd']; [a[3], a[4]] = [a[4], a[3]];

In this approach, we create a new array using the elements we want to swap, and assign it to [a[4], a[3]]. The elements are then simultaneously assigned to the corresponding indices within the original array.

This method yields the same result as Method 1:

1	a // ['a', 'b', 'c', 'd', 'e']

By following either of these methods, you can easily swap two elements within an array in JavaScript.

tags: [“JavaScript”, “array manipulation”, “array elements”, “swap”, “array swap”, “JavaScript tips”]