Home Web Front-end JS Tutorial What are the logical operators in js

What are the logical operators in js

May 06, 2024 am 10:03 AM

JavaScript's logical operators are used for Boolean operations, including: AND operator (&&): compares whether both conditions are true. Or operator (||): Compares two conditions to see if at least one of them is true. Not operator (!): Negates a Boolean value. Zero condition operator (??): Returns the first condition if the first condition is true, otherwise returns the second condition.

What are the logical operators in js

Logical Operators in JavaScript

Logical operators in JavaScript are used to perform Boolean operations, they allow Developers compare and combine Boolean values. The following are the most common logical operators:

1. AND operator (&&):

  • If two operands If both are true, then true is returned, otherwise false is returned.
  • Used to test whether multiple conditions are true.

For example:

const isEligible = (age >= 18) && (hasDriversLicense);
Copy after login

2. Or operator (||):

  • if If any operand is true, then true is returned, otherwise false is returned.
  • Used to test whether at least one of multiple conditions is true.

For example:

const isStudent = (hasStudentCard) || (isUnder18);
Copy after login

3. Not operator (!):

  • will Negate the Boolean value. If the operand is true, then false is returned, and vice versa.
  • Used to invert a condition or convert an expression to a Boolean value.

For example:

const isNotEligible = !(isEligible);
Copy after login

4. Zero conditional operator (??):

  • If the first operand is true, then the first operand is returned, otherwise the second operand is returned.
  • is used to provide a default value, used when the first expression is false.

For example:

const firstName = user.firstName ?? "Guest";
Copy after login

The above is the detailed content of What are the logical operators in js. For more information, please follow other related articles on the PHP Chinese website!

Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

Video Face Swap

Video Face Swap

Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Tools

Notepad++7.3.1

Notepad++7.3.1

Easy-to-use and free code editor

SublimeText3 Chinese version

SublimeText3 Chinese version

Chinese version, very easy to use

Zend Studio 13.0.1

Zend Studio 13.0.1

Powerful PHP integrated development environment

Dreamweaver CS6

Dreamweaver CS6

Visual web development tools

SublimeText3 Mac version

SublimeText3 Mac version

God-level code editing software (SublimeText3)

What should I do if I encounter garbled code printing for front-end thermal paper receipts? What should I do if I encounter garbled code printing for front-end thermal paper receipts? Apr 04, 2025 pm 02:42 PM

Frequently Asked Questions and Solutions for Front-end Thermal Paper Ticket Printing In Front-end Development, Ticket Printing is a common requirement. However, many developers are implementing...

Demystifying JavaScript: What It Does and Why It Matters Demystifying JavaScript: What It Does and Why It Matters Apr 09, 2025 am 12:07 AM

JavaScript is the cornerstone of modern web development, and its main functions include event-driven programming, dynamic content generation and asynchronous programming. 1) Event-driven programming allows web pages to change dynamically according to user operations. 2) Dynamic content generation allows page content to be adjusted according to conditions. 3) Asynchronous programming ensures that the user interface is not blocked. JavaScript is widely used in web interaction, single-page application and server-side development, greatly improving the flexibility of user experience and cross-platform development.

Who gets paid more Python or JavaScript? Who gets paid more Python or JavaScript? Apr 04, 2025 am 12:09 AM

There is no absolute salary for Python and JavaScript developers, depending on skills and industry needs. 1. Python may be paid more in data science and machine learning. 2. JavaScript has great demand in front-end and full-stack development, and its salary is also considerable. 3. Influencing factors include experience, geographical location, company size and specific skills.

How to merge array elements with the same ID into one object using JavaScript? How to merge array elements with the same ID into one object using JavaScript? Apr 04, 2025 pm 05:09 PM

How to merge array elements with the same ID into one object in JavaScript? When processing data, we often encounter the need to have the same ID...

Is JavaScript hard to learn? Is JavaScript hard to learn? Apr 03, 2025 am 12:20 AM

Learning JavaScript is not difficult, but it is challenging. 1) Understand basic concepts such as variables, data types, functions, etc. 2) Master asynchronous programming and implement it through event loops. 3) Use DOM operations and Promise to handle asynchronous requests. 4) Avoid common mistakes and use debugging techniques. 5) Optimize performance and follow best practices.

How to achieve parallax scrolling and element animation effects, like Shiseido's official website?
or:
How can we achieve the animation effect accompanied by page scrolling like Shiseido's official website? How to achieve parallax scrolling and element animation effects, like Shiseido's official website? or: How can we achieve the animation effect accompanied by page scrolling like Shiseido's official website? Apr 04, 2025 pm 05:36 PM

Discussion on the realization of parallax scrolling and element animation effects in this article will explore how to achieve similar to Shiseido official website (https://www.shiseido.co.jp/sb/wonderland/)...

The difference in console.log output result: Why are the two calls different? The difference in console.log output result: Why are the two calls different? Apr 04, 2025 pm 05:12 PM

In-depth discussion of the root causes of the difference in console.log output. This article will analyze the differences in the output results of console.log function in a piece of code and explain the reasons behind it. �...

How to implement panel drag and drop adjustment function similar to VSCode in front-end development? How to implement panel drag and drop adjustment function similar to VSCode in front-end development? Apr 04, 2025 pm 02:06 PM

Explore the implementation of panel drag and drop adjustment function similar to VSCode in the front-end. In front-end development, how to implement VSCode similar to VSCode...

See all articles