1. What is Virtual DOM in React? Virtual DOM is a lightweight copy of the real DOM used by React to improve performance. How it works: React creates a virtual DOM in memory Compares it with previous version (diffing) Updates only changed parts in real DOM Advantage: Faster updates Efficient rendering Improved performance 2. Explain …
React & Node.js Programs
🔷 1. React Counter App (Functional Component) ✅ Question: Create a counter app using functional components in React. 💻 Solution: import React, { useState } from “react”;function Counter() { const [count, setCount] = useState(0); return ( <div style={{ textAlign: “center” }}> <h2>Counter App</h2> <h3>{count}</h3> <button onClick={() => setCount(count + 1)}>Increment</button> <button onClick={() => setCount(count – …
React Redux Counter App (Step-by-Step Example)
📌 INTRODUCTION Redux is one of the most important state management libraries used with React. It helps manage application state in a centralized way. A Counter App using React Redux is a beginner-friendly program that helps you understand: Global state management Redux store Actions Reducers React-Redux integration In this program, we will create a simple …
React Router App (Step-by-Step Navigation Example)
📌 INTRODUCTION Routing is an essential concept in React. It allows users to navigate between different pages or views in a single-page application without reloading the entire website. Using React Router, we can build applications with multiple pages such as: Home About Contact In this program, we will create a simple React Router App and …
React Login Form with Validation using useState
📌 INTRODUCTION A login form is one of the most common components in web applications. It helps users enter their credentials and access a system securely. In React, login forms are usually built using: useState hook Controlled components Form validation In this program, we will develop a login form with validation using React state. 📘 …
React Todo List App (Add + Delete using useState)
📌 INTRODUCTION The Todo List App is one of the most popular beginner projects in React. It helps you understand: State management List rendering Event handling In this program, we will build a Todo app that: Adds tasks Deletes tasks Displays task list dynamically 👉 This is a must-do project for beginners. 📘 PROBLEM STATEMENT …
React Calculator App using useState (Complete Example)
📌 INTRODUCTION Building a calculator is one of the best ways to understand: State management Event handling Dynamic UI updates In this program, we will create a basic calculator app that can: Perform addition, subtraction, multiplication, division Display results dynamically 👉 This is a must-do mini project for React beginners. 📘 PROBLEM STATEMENT 👉 Develop …
React Form Handling using useState (Controlled Components)
📌 INTRODUCTION Handling forms in React is different from traditional HTML. In React, we use controlled components, where form inputs are controlled by state. In this program, we will: Use useState to manage form inputs Handle user input dynamically Understand controlled components 👉 This concept is essential for: Login forms Registration systems Real-world applications 📘 …
React Fetch API using useEffect Hook (Step-by-Step Example)
📌 INTRODUCTION In modern web applications, data is usually fetched from external APIs. React provides the useEffect hook to handle such side effects. In this program, we will: Fetch data from an API Store it using useState Display it dynamically 👉 This is a must-know concept for projects and placements. 📘 PROBLEM STATEMENT 👉 Write …
React Simple Form Component using Props and useStat
📌 INTRODUCTION Forms are an essential part of web applications. In React, form handling is done using state and event handling. In this program, we will: Create a simple form component Handle user input using useState Use props for submission handling 👉 This concept is widely used in: Login forms Registration forms Contact forms 📘 …