Mastering Boolean Values in JavaScript

Introduction

In this lab, we will dive into the concept of boolean values in JavaScript. We will explore how to check whether a given value is a boolean primitive or not using the typeof operator. By the end of this lab, you will have a solid understanding of how to identify boolean values in JavaScript.

Skills Graph

%%%%{init: {'theme':'neutral'}}%%%% flowchart RL javascript(("JavaScript")) -.-> javascript/BasicConceptsGroup(["Basic Concepts"]) javascript/BasicConceptsGroup -.-> javascript/variables("Variables") javascript/BasicConceptsGroup -.-> javascript/data_types("Data Types") javascript/BasicConceptsGroup -.-> javascript/arith_ops("Arithmetic Operators") javascript/BasicConceptsGroup -.-> javascript/comp_ops("Comparison Operators") subgraph Lab Skills javascript/variables -.-> lab-28412{{"Value Is Boolean"}} javascript/data_types -.-> lab-28412{{"Value Is Boolean"}} javascript/arith_ops -.-> lab-28412{{"Value Is Boolean"}} javascript/comp_ops -.-> lab-28412{{"Value Is Boolean"}} end

Checking if a Value is Boolean

To check if a value is a boolean primitive in JavaScript, use the typeof operator with the === comparison operator.

const isBoolean = (val) => typeof val === "boolean";

Here's an example of how to use isBoolean() function to check if a value is boolean:

isBoolean(null); // returns false
isBoolean(false); // returns true

To start practicing coding, open the Terminal/SSH and type node.

Summary

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