array manipulation

If you need to add an item at the beginning of an array in JavaScript, you can use the splice() method. This method allows you to make modifications to an array by specifying the start index, the delete count, and the items you want to add. To add an item at the first position of the array, you can follow these steps: const colors = ['yellow', 'red']; colors.splice(0, 0, 'blue'); // colors === ['blue', 'yellow', 'red'] In the example above, we have an array called colors with two elements: ‘yellow’ and ‘red’....

Learn how to add an item to an array at a specific index in JavaScript. If you want to add an item to an array at a specific position instead of appending it at the end, you can do so by specifying the index where you want to add the item. Note: Array indexes start from 0. So, to add an item at the beginning of the array, you would use index 0....

In JavaScript, flattening an array can be a common task. Fortunately, the ES2019 update introduced two new methods, flat and flatMap, to the Array prototype to simplify this process. However, it’s essential to note that these methods are only supported by more recent versions of browsers such as Firefox 62+, Chrome 69+, Edge 76+, and Safari 12+. If you need to support older browsers, you can consider using Babel to backport your code to a previous ECMAScript version....

JavaScript provides various methods to remove an item from an array. In this article, we will explore the canonical approach as well as other options using plain JavaScript. Here are a few ways to remove an item from an array using JavaScript: By Index: If you know the index of the item you want to remove, you can use the slice() method to create a new array without mutating the original one....

Replacing an item in an array in JavaScript is a common operation when working with arrays. This can be easily achieved using a simple assignment if you know the index of the item. Here’s an example: const items = ['a', 'b', 'c', 'd', 'e', 'f']; const i = 2; items[i] = '--NEW-ITEM--'; console.log(items); //[ 'a', 'b', '--NEW-ITEM--', 'd', 'e', 'f' ] In the code above, we have an array called items with multiple elements....

Reversing a JavaScript array can be done using a few different methods. In this article, we will explore the different ways to achieve this. Let’s start with an example array called list: const list = [1, 2, 3, 4, 5]; The easiest and most intuitive way to reverse an array is by using the built-in reverse() method. This method directly alters the original array, so you can call it directly on list:...

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:...