Value Is Nil

Introduction

In this lab, we will delve into the concept of checking if a specified value is null or undefined. We will explore the isNil() function, which makes use of the strict equality operator to perform the check, and we will see how it can be used in practical scenarios to improve the reliability and robustness of our code.

Skills Graph

How to Check if a Value is Null or Undefined in JavaScript

To determine if a value is null or undefined in JavaScript, you can use the strict equality operator (===). Here's an example code snippet that checks if the specified value is null or undefined:

const isNil = (val) => val === undefined || val === null;

You can use this function to check if a value is null or undefined, like this:

isNil(null); // true
isNil(undefined); // true
isNil(""); // false

To start practicing coding in JavaScript, you can open the Terminal/SSH and type node.

Summary

Congratulations! You have completed the Value Is Nil lab. You can practice more labs in LabEx to improve your skills.