ReactJS is a JavaScript library for building user interfaces with features such as JSX, and virtual DOM for efficient updates and unidirectional data flow.
I’ll start by giving a simple example of what a runtime error would look like in a React application. InApp.jsI’ve written a simple program that renders the properties ofuserobject to the screen. import { useState } from 'react'; import './App.css'; function App() { const [user...
We want to optimize the performance of the handleIncrement function, which is passed down to the ChildComponent. We import the necessary hooks from React: useState and useCallback. Inside the App component, we define the handleIncrement callback function using the useCallback hook. This function...
To use the state inside a functional component, the “useState” hook is used. For eg: importReact, {useState}from"react";constDemoComponent =()=>{const[value, setValue] = useState(1);return({value}setValue((value + 1))}>Increment Value); };Code language:JavaScript(javascript) As you...
Let's explore a basic example of a switching component in React.import React, { useState } from 'react'; const SwitchingComponent = () => { // State to manage the active tab const [activeTab, setActiveTab] = useState('tab1'); // Function to handle tab change const handleTabChange ...
React components can have state, which represents data that can change over time. You can use the useState hook (for functional components) or the setState method (for class components) to manage state within a component. React components have lifecycle methods that allow you to hook into vario...
import React, { useContext } from 'react'; const AuthContext = React.createContext(); const AuthProvider = ({ children }) => { const [user, setUser] = React.useState(null); const login = (userData) => setUser(userData); const logout = () => setUser(null); return ( <AuthContex...
Now in ourApp.jswe can simply import the new function and start using it immediately. import { useEffect, useState } from "react"; import { fetchPerson } from "./fetcher"; function App() { const [personID, setPersonID] = useState(1); ...
Step 1? Create a React application. Step 2? In the application's project directory, run the below command to install the ?axios' NPM package in the project. npm i axios Step 3? In the App() component, use the ?useState' hooks to update the messages we receive from the server. ...
Things to do and look up: - `npx create-react-app --typescript` which installs a lot of stuff - Components - JSX - The difference between Props and State - Function Components and the useState hook And some time later: - hooks in general, like useEffect and custom hooks - refs and ...