React Project Setup

Use Vite or Create React App to initialize your project.

# Using Vite
npm create vite@latest my-react-app
cd my-react-app
npm install
npm run dev

🔧 2. Basic Project Commands

Command Description

Command	Description
npm install	Install all dependencies from package.json
npm run dev	Start development server (Vite)
npm start	Start development server (CRA)
npm run build	Build app for production
npm run preview	Preview production build (Vite)
npm test	Run tests (CRA has this by default)

📁 Typical React Folder Structure

my-app/
├── node_modules/          # All installed npm packages
├── public/                # Static assets (like index.html, favicon, images)
│   └── index.html         # Main HTML file (only one)
├── src/                   # All React code lives here
│   ├── assets/            # Static files (images, fonts, etc.)
│   ├── components/        # Reusable components (Navbar, Button, etc.)
│   ├── pages/             # Different views or route pages (Home, About, etc.)
│   ├── hooks/             # Custom React hooks (optional but clean)
│   ├── context/           # Context API files (if using global state)
│   ├── App.jsx            # Root component
│   ├── main.jsx           # Entry point - connects React with DOM
│   └── index.css          # Global CSS or Tailwind import
├── .gitignore             # Ignore files for Git
├── package.json           # Project metadata + dependencies
├── tailwind.config.js     # Tailwind config (if used)
├── postcss.config.js      # Tailwind PostCSS settings
├── vite.config.js         # Vite configuration file
└── README.md              # Project description

🧩 Key Files Explained

File/Folder	Purpose
public/index.html	Only HTML file, React mounts here via div#root.
src/main.jsx	Entry point. Renders <App /> inside #root.
src/App.jsx	Main component. Acts like the layout or router wrapper.
src/components/	Contains reusable UI components (e.g., Button, Navbar).
src/pages/	Contains full pages/views (e.g., Home, About).
src/assets/	Images, logos, fonts, or static files.
src/context/	Context API files for managing global state.
src/hooks/	Custom reusable logic (e.g., useFetch, useAuth).

⚙️ Recommended VS Code Extensions & Use Cases

Extension	Use Case
Thunder Client	Lightweight REST client for testing APIs directly in VS Code.
TailwindCSS IntelliSense	Autocomplete, syntax highlighting, and linting for Tailwind CSS classes.
Postman	Advanced API testing and monitoring (external app, complements Thunder).
Auto Import	Automatically imports components, hooks, and functions as you type.
Auto Close Tag	Automatically closes HTML/JSX tags when you type an opening tag.
Auto Rename Tag	Automatically renames paired HTML/JSX tags when one is changed.
Reactjs Code Snippets	Shortcut snippets for fast writing of common React code blocks.
Path Intellisense	Autocompletes file paths when importing modules or assets.
npm Intellisense	Autocompletes npm packages in import statements.
ESLint	Identifies and fixes linting issues in JavaScript/TypeScript code.
VSCode React Refactor	Provides React-specific refactor tools like extracting components.
vscode-icons	Adds icons to files and folders for better visual navigation.

✅ Week 1 Summary: Learn the Basics

✅ React Learning - Week 1 Summary Table

Day	Topic	Description	Example
1	What is React?	Introduction to React, its use cases, and SPA (Single Page Applications).	npx create-react-app my-app
2	Setting up React Project	Installing Node.js, creating a project using Vite or CRA, project structure.	npm create vite@latest
3	JSX Syntax	Writing JSX: HTML-like syntax in JS, expressions, fragments, etc.	<h1>Hello, {name}</h1>
4	Functional Components	Create and use functional components.	function Header() { return <h1 /> }
5	Props (Properties)	Passing data to components using props.	<User name="Mamun" />
6	useState Hook	Adding state to functional components.	const [count, setCount] = useState(0)
7	Mini Project + Recap	Counter App using useState and props.	A working click counter with buttons

Concept What You’ll Learn

1. JSX Write HTML in JavaScript
2. Functional Components Build simple, reusable pieces of UI
3. Props Pass data to components
4. State with useState() Make components dynamic
5. Events Handle user actions like click, input change

📘 DAY 1: JSX (JavaScript + XML)

JSX lets you write HTML inside JavaScript:

function App() {
  const name = "Mamun";
  return (
    <div>
      <h1>Hello, {name}!</h1>
      <p>This is your first JSX.</p>
    </div>
  );
}

export default App;

✅ Rules of JSX:

• Must return one parent element
• Use className instead of class
• JavaScript expressions are written inside {}

📘 DAY 2: Functional Components

A component is a function that returns JSX.

function Header() {
  return <h2>This is Header</h2>;
}

function App() {
  return (
    <div>
      <Header />
      <p>Welcome to the app!</p>
    </div>
  );
}

✅ Split your UI into small, reusable components.

📘 DAY 3: Props (Passing Data to Components)

Props = Parameters for components

function Greeting(props) {
  return <h2>Hello, {props.name}!</h2>;
}

function App() {
  return (
    <div>
      <Greeting name="Mamun" />
      <Greeting name="Sadia" />
    </div>
  );
}

✅ Props are read-only. You can pass strings, numbers, arrays, even functions.

📘 DAY 4: useState() Hook (State Management)

State allows a component to remember values.

import { useState } from "react";

function Counter() {
  const [count, setCount] = useState(0);

  return (
    <div>
      <p>Count: {count}</p>
      <button onClick={() => setCount(count + 1)}>Increment</button>
    </div>
  );
}

export default Counter;

✅ useState() returns:

count → current value

setCount() → function to update it

📘 DAY 5: Events in React

React uses onClick, onChange, etc.

function ButtonClicker() {
  function handleClick() {
    alert("Button clicked!");
  }

  return <button onClick={handleClick}>Click Me</button>;
}

Input example:

function InputDemo() {
  const [text, setText] = useState("");

  return (
    <input
      type="text"
      value={text}
      onChange={(e) => setText(e.target.value)}
    />
  );
}

📘 DAY 6: Practice Task

✅ Build a small app:

// App.jsx
import Greeting from "./Greeting";
import Counter from "./Counter";

function App() {
  return (
    <div>
      <Greeting name="Mamun" />
      <Counter />
    </div>
  );
}

Create Greeting.jsx and Counter.jsx as explained earlier.

📘 DAY 7: Review + Quiz

✅ Quiz: What is JSX? What is the purpose of useState()? Can props be changed inside a component? How do you handle a button click in React?

🛠️ Bonus: Folder Structure So Far

/src
├── App.jsx
├── Greeting.jsx
├── Counter.jsx
└── index.css

🔔 Next: If you're ready, I can now move to Week 2: useEffect(), Lists, Forms, and controlled components. Want to continue?

---

✅ Week 2 Summary: Dynamic Behavior with Hooks & Forms Day Focus Topics Covered 1 useEffect() Hook Side effects, API calls, lifecycle behavior 2 Lists & Keys Loop through data using map(), handle keys 3 Conditional Rendering Show/hide content based on conditions 4 Forms in React Controlled inputs using useState() 5 Form Submission Handle submit events, basic validation 6 Mini Project Day Build a "To-Do App" or "Contact Form" 7 Recap + Quiz Review concepts and test your understanding

📘 DAY 1: useEffect() – React's Lifecycle Hook Used for side effects, like:

Fetching data from an API

Setting document title

Setting timers

jsx Copy Edit import { useState, useEffect } from "react";

function EffectDemo() { const [count, setCount] = useState(0);

useEffect(() => { document.title = Clicked ${count} times; }, [count]);

return (

You clicked {count} times.

<button onClick={() => setCount(count + 1)}>Click

); } ✅ useEffect(() => {}, [dependency]) runs when dependency changes.

📘 DAY 2: Rendering Lists & Keys jsx Copy Edit function ListDemo() { const items = ["Apple", "Banana", "Mango"]; return (

{items.map((item, index) => (
• {item}
))}

); } ✅ Keys must be unique — helps React efficiently update UI.

📘 DAY 3: Conditional Rendering jsx Copy Edit function UserGreeting({ isLoggedIn }) { return (

{isLoggedIn ?

Welcome back!

:

Please log in.

}

); } ✅ You can use if, ternary (?), or && to conditionally show components.

📘 DAY 4: Controlled Forms Controlled = Form values are stored in useState().

jsx Copy Edit function ControlledInput() { const [name, setName] = useState("");

return (

<input type="text" value={name} onChange={(e) => setName(e.target.value)} />

Your name is: {name}

); } ✅ Input field is always in sync with the state.

📘 DAY 5: Form Submission with Validation jsx Copy Edit function ContactForm() { const [email, setEmail] = useState("");

const handleSubmit = (e) => { e.preventDefault(); if (!email.includes("@")) { alert("Invalid email!"); return; } alert("Submitted: " + email); };

return (

<input type="email" value={email} onChange={(e) => setEmail(e.target.value)} /> Submit ); } 📘 DAY 6: Mini Project — To-Do App 🔧 To-Do App Overview: Input field to add a task

Display task list

Option to delete tasks

jsx Copy Edit function TodoApp() { const [task, setTask] = useState(""); const [tasks, setTasks] = useState([]);

const addTask = (e) => { e.preventDefault(); if (!task.trim()) return; setTasks([...tasks, task]); setTask(""); };

const deleteTask = (index) => { setTasks(tasks.filter((_, i) => i !== index)); };

return (

<input value={task} onChange={(e) => setTask(e.target.value)} /> Add Task

{tasks.map((t, i) => (
• {t} <button onClick={() => deleteTask(i)}>❌
))}

); } 📘 DAY 7: Review + Quiz 🔁 Review Topics: useEffect with dependency array

Mapping and keys

Controlled vs uncontrolled components

Form submit and validation

❓ Quiz: What is the purpose of useEffect()?

Why do we need a unique key in lists?

What's a controlled component?

How do you prevent page reload on form submit?

What's the difference between == and === in React (JS)?

✅ Folder Structure So Far bash Copy Edit /src ├── App.jsx ├── components │ ├── Counter.jsx │ ├── Greeting.jsx │ ├── TodoApp.jsx │ └── ContactForm.jsx 🚀 Ready for Week 3? Topics for Week 3:

React Router DOM

Project pages

Navigation

URL parameters

Reusable components

Would you like me to start Week 3 now?

You said: now week 3

ChatGPT said: Perfect, AN Mamun! Welcome to Week 3 — this week is all about building multi-page applications with React Router DOM, learning how to navigate, and using URL parameters. You'll learn how to build a real-world app with routing!

---

✅ Week 3 Summary: React Router & Navigation Day Topic Description 1 Intro to React Router DOM Install and configure basic routing 2 Routes and Navigation Define routes, build navigation with or 3 Dynamic Routes with Params Use route parameters like /user/:id 4 useParams and useNavigate Access URL params and programmatically navigate 5 Nested Routes Render child components in parent routes 6 Mini Project Day Create a Blog or Product Detail site with routing 7 Review + Quiz Recap and test your understanding

📘 DAY 1: Install & Setup React Router 1️⃣ Install: bash Copy Edit npm install react-router-dom 2️⃣ Setup BrowserRouter: jsx Copy Edit // main.jsx or index.js import { BrowserRouter } from "react-router-dom"; import App from "./App";

ReactDOM.createRoot(document.getElementById("root")).render( ); 📘 DAY 2: Define Routes & Navigation jsx Copy Edit // App.jsx import { Routes, Route, Link } from "react-router-dom"; import Home from "./pages/Home"; import About from "./pages/About";

function App() { return (

🏠 Home | ℹ️ About

  <Routes>
    <Route path="/" element={<Home />} />
    <Route path="/about" element={<About />} />
  </Routes>
</div>

); } ✅ Create files:

jsx Copy Edit // pages/Home.jsx export default function Home() { return

Welcome to the Home Page

; }

// pages/About.jsx export default function About() { return

This is the About Page

; } 📘 DAY 3: Dynamic Routing with Params jsx Copy Edit // App.jsx <Route path="/user/:username" element={} /> jsx Copy Edit // pages/User.jsx import { useParams } from "react-router-dom";

function User() { const { username } = useParams(); return

Hello, {username}!

; } 🧠 Example URL:

bash Copy Edit http://localhost:5173/user/mamun → shows: Hello, mamun! 📘 DAY 4: useNavigate & useParams jsx Copy Edit // Navigate after login import { useNavigate } from "react-router-dom";

function Login() { const navigate = useNavigate(); const handleLogin = () => { // login logic here... navigate("/dashboard"); }; return Login; } ✅ useParams() → get URL values ✅ useNavigate() → redirect programmatically

📘 DAY 5: Nested Routes (Inside Layouts) jsx Copy Edit <Route path="/dashboard" element={}> <Route path="profile" element={} /> <Route path="settings" element={} /> In Dashboard.jsx:

jsx Copy Edit import { Outlet } from "react-router-dom";

export default function Dashboard() { return (

Dashboard

); } URL:

/dashboard/profile → shows profile

/dashboard/settings → shows settings

📘 DAY 6: Mini Project — Blog App Features: Home Page → List of blog posts

Post Page → Dynamic route to view post by ID

About Page

Add useParams, useNavigate

📘 DAY 7: Review + Quiz 🔁 Review Topics: Install & setup React Router DOM

Use of Route, Link, useParams, useNavigate

Dynamic routes & nested routes

❓ Quiz: How do you define a dynamic route in React?

Difference between and ?

What does useParams() return?

How to programmatically redirect in React?

What’s the use of ?

📁 Suggested Folder Structure bash Copy Edit /src ├── App.jsx ├── main.jsx ├── /pages │ ├── Home.jsx │ ├── About.jsx │ ├── User.jsx │ ├── Dashboard.jsx │ ├── Profile.jsx │ └── Settings.jsx ✅ Done with Week 3! React Router unlocks the power of real app structure. Ready for Week 4?

Topics next week:

Props Drilling & Lifting State Up

Component Reusability

React Context API (avoid prop drilling)

Custom Hooks

Would you like to begin Week 4 now?

---

✅ Week 4 Summary: Data Flow, Props, and Context API Day Topic Description 1 Props Drilling Passing data through multiple levels of components 2 Lifting State Up Moving state to a common ancestor to share across components 3 Component Reusability Building flexible, reusable components with props 4 Intro to Context API Create and use global state with React.createContext() 5 useContext Hook Access context without manually passing props 6 Mini Project Day Theme toggler or simple user profile manager using Context API 7 Review + Quiz Recap week’s learning and test your understanding

📘 DAY 1: Props Drilling Props drilling is when you pass data through many nested components unnecessarily.

jsx Copy Edit function App() { return ; }

function Parent({ user }) { return ; }

function Child({ user }) { return ; }

function GrandChild({ user }) { return

Hello, {user}

; } 🔴 Problem: Passing user through every level ✅ Solution: React Context API

📘 DAY 2: Lifting State Up Shared state should live in the nearest common parent.

jsx Copy Edit function App() { const [count, setCount] = useState(0); return ( <> </> ); }

function CounterDisplay({ count }) { return

Count: {count}

; }

function CounterButton({ setCount }) { return <button onClick={() => setCount(c => c + 1)}>Increase; } 🔼 State is lifted to so both components can access it.

📘 DAY 3: Component Reusability Make components flexible by using props:

jsx Copy Edit function Button({ text, onClick, color }) { return ( <button onClick={onClick} style={{ backgroundColor: color }}> {text} ); }

// Usage 📘 DAY 4: Intro to Context API Avoid prop drilling by using Context:

jsx Copy Edit import { createContext, useState } from "react";

export const UserContext = createContext();

export function UserProvider({ children }) { const [user, setUser] = useState("Mamun");

return ( <UserContext.Provider value={{ user, setUser }}> {children} </UserContext.Provider> ); } Wrap your app:

jsx Copy Edit // main.jsx <React.StrictMode> </React.StrictMode> 📘 DAY 5: useContext Hook Access context values easily:

jsx Copy Edit import { useContext } from "react"; import { UserContext } from "../context/UserContext";

function Profile() { const { user, setUser } = useContext(UserContext);

return (

Logged in as: {user}

<button onClick={() => setUser("AN Mamun")}>Change User

); } ✅ No need for props at every level!

📘 DAY 6: Mini Project – Theme Toggler Build a simple theme switcher:

Create ThemeContext.js

Provide dark/light mode

Toggle with button

Apply styles conditionally

jsx Copy Edit // ThemeContext.js export const ThemeContext = createContext();

export function ThemeProvider({ children }) { const [darkMode, setDarkMode] = useState(false);

return ( <ThemeContext.Provider value={{ darkMode, setDarkMode }}> {children} </ThemeContext.Provider> ); } Use it:

jsx Copy Edit const { darkMode, setDarkMode } = useContext(ThemeContext);

<button onClick={() => setDarkMode(!darkMode)}> Toggle Theme 📘 DAY 7: Review + Quiz ✅ Key Concepts Props drilling vs Context

Lifting state

Reusable components

Using useContext instead of passing props

❓ Quiz What is props drilling?

Why and when to use lifting state up?

How does createContext() work?

What is useContext() used for?

How do you make a reusable component?

Suggested File Structure (Context Example) bash Copy Edit /src ├── App.jsx ├── main.jsx ├── /components │ ├── Profile.jsx │ └── ThemeToggle.jsx ├── /context │ ├── UserContext.js │ └── ThemeContext.js 🎉 Week 4 Completed! You're now handling:

Reusability

State sharing

Global state via context

🚀 Ready for Week 5?

Week 5:

Forms in React

Controlled vs Uncontrolled Components

Form Validation

React Hook Form

Would you like to start Week 5 now?

"# react.jsx"