JavaScript concept is a high-level, dynamic, multi-paradigm programming language used for web development, creating interactive user interfaces, and building server-side applications. It was created in 1995 by Brendan Eich while he was working at Netscape Communications Corporation. Today, it is one of the most popular programming languages in the world, with a large and active developer community.
Oops is used in JavaScript and it is a client-side language, meaning that it runs in the browser and can interact with HTML and CSS to create dynamic and responsive web pages. It can also be used on the server side, with Node.js, to create powerful and scalable back-end applications.
JavaScript is an interpreted language, meaning that it doesn’t need to be compiled before running. It is also dynamically typed, meaning that variables can hold different types of data at different times during execution. JavaScript supports functional, object-oriented, and imperative programming paradigms. This article will help you understand JavaScript fundamentals and code better.
8 Advance JavaSCript concepts
Here is the list of the top 8 advanced concepts of JavaScript that you must know before starting a project. These advanced concepts will help JavaScript developers to understand this language better.
1. Closures
Closures are a powerful concept in JavaScript that allows you to create private variables and methods inside a function. It is achieved by creating a function inside another function and returning it. Here is an example:
| function outerFunction() {
var outerVar = “I am outer”; function innerFunction() { var innerVar = “I am inner”; console.log(outerVar, innerVar); } return innerFunction; } var inner = outerFunction(); inner(); |
2. Promises
Promises are a way to handle asynchronous operations in JavaScript. Promises are objects that represent the eventual completion or failure of an asynchronous operation and allow you to attach callbacks to them. Here is an example:
| function getData() {
return new Promise((resolve, reject) => { setTimeout(() => { resolve(“Data fetched successfully!”); }, 2000); }); } getData().then((data) => { console.log(data); }); |
3. Async/await
Async/await is a modern syntax for handling asynchronous operations in JavaScript. Async/await makes it easier to write asynchronous code in a synchronous way. Here is an example:
| function getData() {
return new Promise((resolve, reject) => { setTimeout(() => { resolve(“Data fetched successfully!”); }, 2000); }); } async function main() { const data = await getData(); console.log(data); } main(); |
4. Generators
Generators are functions that can be paused and resumed at any point. Generators are defined using the function* keyword and the yield keyword is used to pause the function. Here is an example:
| function* generatorFunction() {
yield 1; yield 2; yield 3; } const generator = generatorFunction(); console.log(generator.next().value); console.log(generator.next().value); console.log(generator.next().value); |
5. Proxy
Proxy is a powerful feature in JavaScript that allows you to intercept and customize the behavior of objects. Proxy is defined using the Proxy object and a handler object is passed to it. Here is an example:
| const person = {
name: “John”, age: 30, }; const handler = { get: function (target, prop) { console.log(`Getting ${prop} property`); return target[prop]; }, set: function (target, prop, value) { console.log(`Setting ${prop} property to ${value}`); target[prop] = value; }, }; const proxy = new Proxy(person, handler); proxy.name; proxy.age = 40; console.log(person); |
6. Maps
Maps are a new data structure introduced in ES6 that allows you to store key-value pairs. Unlike objects, maps can use any type of key, not just strings. Here is an example:
| const map = new Map();
map.set(“name”, “John”); map.set(“age”, 30); console.log(map.get(“name”)); console.log(map.get(“age”)); |
7. Sets
Sets are another new data structure introduced in ES6 that allows you to store unique values. Here is an example:
| const set = new Set();
set.add(1); set.add(2); set.add(3); console.log(set.has(1)); console.log(set.has(4)); |
8. Spread operator:
The spread operator is a syntax for spreading the elements of an array or object into another array or object. Here is an example:
| const arr1 = [1, 2, 3];
const arr2 = [4, 5, 6]; const arr3 |
Final Thought
The best part about learning the advanced concepts of JavaScript is that it enables you to build an application more user-friendly and interactive. JavaScript is considered the best programming language for building an advance and user-friendly web application.
