Checking if a key exists in a JavaScript object involves verifying whether a specific property is defined within the object. This practice ensures data integrity, prevents errors, and facilitates smooth program execution by confirming property existence before accessing or manipulating it....

We have given an input string and the task is to reverse the input string in JavaScript. It is a very common question asked in a JavaScript interview. There are various methods to reverse a string in JavaScript, which are described below with examples....

The filter() method creates a new array filled with elements that pass a test provided by a function. It’s a powerful tool for selectively extracting data from arrays based on specified criteria. Notably, it ignores empty elements, enhancing its efficiency and reliability in data filtering operations....

Node.js uses the CommonJS module system to organize code. This means when you want to use code from other files, you use methods like ‘require’. Additionally, Node.js also supports ‘ES6 import and export’ for this purpose. Let us understand in detail....

There are a lot of ways in which we can show a loading div but we have figured out the most optimal solution for you and that too in pure vanilla JavaScript. We will use the document.readyState property. When the value of this property changes, a readystatechange event fires on the document object....

In this article, we will learn to get the child element of the parent using JavaScript. Given an HTML document, the task is to select a particular element and get all the child elements of the parent element with the help of JavaScript....

A two-dimensional array in JavaScript is an array of arrays, used to represent data in a matrix or grid format. It’s useful for organizing data in rows and columns, such as tables, spreadsheets, or game boards, facilitating complex data manipulation and storage....

The match() method checks if a string fits a pattern defined by a regular expression. It gives back an array with the matches it finds. If there’s no match, it returns null. YOu can often use this method to find specific patterns within strings....

The Number.isInteger() method in JavaScript is a useful checking whether a number is a whole number or not. When you use it, it gives you a simple answer: ‘true‘ if the number is a whole number and ‘false‘ if it’s not. This can be really useful when you’re working with numbers and need to make sure they’re exactly whole, without any fractions or decimals....

Sets in JavaScript are collections of unique values, meaning no duplicates are allowed. They provide efficient ways to store and manage distinct elements. Sets support operations like adding, deleting, and checking the presence of items, enhancing performance for tasks requiring uniqueness....

We’ll learn how to display images when someone clicks on them using HTML. We’ll also use a bit of JavaScript to make our web pages more dynamic. We’ll go through a few easy ways to do this, so you can choose the one that works best for you. Let’s get started!...

Node.js is an open-source and cross-platform JavaScript runtime environment that can also be used to read from a file and write to a file which can be in txt, ods, xlsx, docx, etc format....