In JavaScript, operators are special symbols or keywords used to perform operations on values and variables. They allow us to manipulate data and control the flow of the code. Let’s break down the most commonly used types of operators and their purposes:
1?? Assignment Operators (=)
The assignment operator is used to assign values to variables.
? Example:
let x = 10 // Assigns the value 10 to variable x let y = 5 // Assigns the value 5 to variable y
2?? Arithmetic Operators
Arithmetic operators perform basic mathematical operations on numbers.
- (Addition)
- - (Subtraction)
- * (Multiplication)
- / (Division)
- % (Modulus – remainder of division)
- ** (Exponentiation (ES2016))
- (Increment)
- -- (Decrement)
? Example:
console.log("x + y = " + (x + y)) // Output: x + y = 15
console.log("x - y = " + (x - y)) // Output: x - y = 5
console.log("x / y = " + (x / y)) // Output: x / y = 2
console.log("x * y = " + (x * y)) // Output: x * y = 50
console.log("x % y = " + (x % y)) // Output: x % y = 0
console.log("(x**y) = " + (x**y)) // Output: (x**y) = 100000
console.log("(++x) = " + (++x)) // Output: (++x) = 11
console.log("(x++) = " + (x++)) // Output: (x++) = 11
console.log("(--y) = " + (--y)) // Output: (--y) = 4
console.log("(y--) = " + (y--)) // Output: (y--) = 4
3?? Comparison Operators
Comparison operators compare two values and return a Boolean (true or false). These are often used in loops and branching statements.
- == (Equal to)
- === (Strictly equal to)
- != (Not equal to)
- !== (Strictly not equal to)
- < (Less than)
- > (Greater than)
- <= (Less than or equal to)
- >= (Greater than or equal to)
? Example:
console.log("(x == y) = " + (x == y)) // Output: (x == y) = false
console.log("(x != y) = " + (x != y)) // Output: (x != y) = true
// Compares datatypes also
console.log("(x === y) = " + (x === y)) // Output: (x === y) = false
// Compares datatypes also
console.log("(x !== y) = " + (x !== y)) // Output: (x !== y) = true
console.log("(x > y) = " + (x > y)) // Output: (x > y) = true
console.log("(x >= y) = " + (x >= y)) // Output: (x >= y) = true
console.log("(y < x) = " + (y < x)) // Output: (y < x) = true
console.log("(y <= x) = " + (y <= x)) // Output: (y <= x) = true
4?? Logical Operators
Logical operators are used to perform logical operations and return a Boolean value (true or false).
- && (Logical AND)
- || (Logical OR)
- ! (Logical NOT)
? Example:
let isValidNumber = (x > 8 && 8 > y) // If both condition are correct returns true otherwise false
console.log("(x > 8 && 8 > y) = " + isValidNumber) // Output: (x > 8 && 8 > y) = true
let isValidCheck = (x > 20 || 8 > y) // If one of condition is correct returns true otherwise false
console.log("(x > 20 || 8 > y) = " + isValidCheck) // Output: (x > 20 || 8 > y) = true
let isValid = false
console.log("(!isValid) = " + !isValid) // Output: (!isValid) = true
5?? String Operators
The operator is versatile and can be used with strings for concatenation (joining two strings). When used with numbers, it performs addition.
? Example:
// Concatenation
console.log("Richa " + "webDev") // Output: Richa webDev
// Addition
console.log(10 + 5) // Output: 15
6?? Ternary Operator (? :)
The ternary operator is a concise way to perform conditional checks. It returns one value if the condition is true and another if it’s false.
? Syntax:
condition ? valueIfTrue : valueIfFalse;
? Example:
const isEven = 10 % 2 === 0 ? "Number is even" : "Number is old"
console.log("isEven = " + isEven) // Output: isEven = Number is even
? Brain teaser
Explain why the output of the code snippet, involving the num , --num, and num-- operations, results in the value 21. Comment down below.
let num = 20
console.log("num = " + num) // Output: (++num) = 21
console.log("(++num) = " + (++num)) // Output: (++num) = 21
console.log("(num++) = " + (num++)) // Output: (num++) = 21
console.log("(--num) = " + (--num)) // Output: (--num) = 21
console.log("(num--) = " + (num--)) // Output: (num--) = 21
Output:
num = 20 (++num) = 21 (num++) = 21 (--num) = 21 (num--) = 21
Conclusion
JavaScript operators are fundamental building blocks that help you write effective and efficient code. By mastering them, you can perform a wide range of operations, from simple assignments to complex logical checks. Experiment with these operators to better understand their behavior!
Happy coding ?
The above is the detailed content of Understanding JavaScript Operators. For more information, please follow other related articles on the PHP Chinese website!
Hot AI Tools
Undress AI Tool
Undress images for free
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Clothoff.io
AI clothes remover
Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!
Hot Article
Hot Tools
Notepad++7.3.1
Easy-to-use and free code editor
SublimeText3 Chinese version
Chinese version, very easy to use
Zend Studio 13.0.1
Powerful PHP integrated development environment
Dreamweaver CS6
Visual web development tools
SublimeText3 Mac version
God-level code editing software (SublimeText3)
Hot Topics
How to work with dates and times in js?
Jul 01, 2025 am 01:27 AM
The following points should be noted when processing dates and time in JavaScript: 1. There are many ways to create Date objects. It is recommended to use ISO format strings to ensure compatibility; 2. Get and set time information can be obtained and set methods, and note that the month starts from 0; 3. Manually formatting dates requires strings, and third-party libraries can also be used; 4. It is recommended to use libraries that support time zones, such as Luxon. Mastering these key points can effectively avoid common mistakes.
Why should you place tags at the bottom of the ?
Jul 02, 2025 am 01:22 AM
PlacingtagsatthebottomofablogpostorwebpageservespracticalpurposesforSEO,userexperience,anddesign.1.IthelpswithSEObyallowingsearchenginestoaccesskeyword-relevanttagswithoutclutteringthemaincontent.2.Itimprovesuserexperiencebykeepingthefocusonthearticl
What is event bubbling and capturing in the DOM?
Jul 02, 2025 am 01:19 AM
Event capture and bubble are two stages of event propagation in DOM. Capture is from the top layer to the target element, and bubble is from the target element to the top layer. 1. Event capture is implemented by setting the useCapture parameter of addEventListener to true; 2. Event bubble is the default behavior, useCapture is set to false or omitted; 3. Event propagation can be used to prevent event propagation; 4. Event bubbling supports event delegation to improve dynamic content processing efficiency; 5. Capture can be used to intercept events in advance, such as logging or error processing. Understanding these two phases helps to accurately control the timing and how JavaScript responds to user operations.
How can you reduce the payload size of a JavaScript application?
Jun 26, 2025 am 12:54 AM
If JavaScript applications load slowly and have poor performance, the problem is that the payload is too large. Solutions include: 1. Use code splitting (CodeSplitting), split the large bundle into multiple small files through React.lazy() or build tools, and load it as needed to reduce the first download; 2. Remove unused code (TreeShaking), use the ES6 module mechanism to clear "dead code" to ensure that the introduced libraries support this feature; 3. Compress and merge resource files, enable Gzip/Brotli and Terser to compress JS, reasonably merge files and optimize static resources; 4. Replace heavy-duty dependencies and choose lightweight libraries such as day.js and fetch
A definitive JS roundup on JavaScript modules: ES Modules vs CommonJS
Jul 02, 2025 am 01:28 AM
The main difference between ES module and CommonJS is the loading method and usage scenario. 1.CommonJS is synchronously loaded, suitable for Node.js server-side environment; 2.ES module is asynchronously loaded, suitable for network environments such as browsers; 3. Syntax, ES module uses import/export and must be located in the top-level scope, while CommonJS uses require/module.exports, which can be called dynamically at runtime; 4.CommonJS is widely used in old versions of Node.js and libraries that rely on it such as Express, while ES modules are suitable for modern front-end frameworks and Node.jsv14; 5. Although it can be mixed, it can easily cause problems.
How to make an HTTP request in Node.js?
Jul 13, 2025 am 02:18 AM
There are three common ways to initiate HTTP requests in Node.js: use built-in modules, axios, and node-fetch. 1. Use the built-in http/https module without dependencies, which is suitable for basic scenarios, but requires manual processing of data stitching and error monitoring, such as using https.get() to obtain data or send POST requests through .write(); 2.axios is a third-party library based on Promise. It has concise syntax and powerful functions, supports async/await, automatic JSON conversion, interceptor, etc. It is recommended to simplify asynchronous request operations; 3.node-fetch provides a style similar to browser fetch, based on Promise and simple syntax
What are best practices for writing clean and maintainable JavaScript code?
Jun 23, 2025 am 12:35 AM
To write clean and maintainable JavaScript code, the following four points should be followed: 1. Use clear and consistent naming specifications, variable names are used with nouns such as count, function names are started with verbs such as fetchData(), and class names are used with PascalCase such as UserProfile; 2. Avoid excessively long functions and side effects, each function only does one thing, such as splitting update user information into formatUser, saveUser and renderUser; 3. Use modularity and componentization reasonably, such as splitting the page into UserProfile, UserStats and other widgets in React; 4. Write comments and documents until the time, focusing on explaining the key logic and algorithm selection
var vs let vs const: a quick JS roundup explainer
Jul 02, 2025 am 01:18 AM
The difference between var, let and const is scope, promotion and repeated declarations. 1.var is the function scope, with variable promotion, allowing repeated declarations; 2.let is the block-level scope, with temporary dead zones, and repeated declarations are not allowed; 3.const is also the block-level scope, and must be assigned immediately, and cannot be reassigned, but the internal value of the reference type can be modified. Use const first, use let when changing variables, and avoid using var.
