1. Introduction to React Router

React Router is a library for handling routing in React applications. It allows your app to navigate between different components and views without a full-page reload, making the user experience seamless.

2. Basic Setup

Start by installing react-router-dom:

npm install react-router-dom

Set up basic routing using BrowserRouter, Routes, and Route:

import React from 'react';
import { BrowserRouter as Router, Routes, Route, Link } from 'react-router-dom';

const Home = () => 
Home
;
const About = () => 
About
;

const App = () => {
  return (
    } />
        } />
      
  );
};

export default App;

3. Nested Routing

For more complex apps, you can nest routes. Here’s how to set up nested routes in a parent component:

import React from 'react';
import { BrowserRouter as Router, Routes, Route, Link } from 'react-router-dom';

const Dashboard = () => 
Dashboard Home
;
const Profile = () => 
Your Profile
;

const DashboardLayout = () => {
  return (
    

      } />
        } />
      
  );
};

const App = () => {
  return (
    } />
      
  );
};

export default App;

4. Dynamic Routing

Dynamic routing allows you to pass parameters in the URL. Here’s how to define and access a dynamic route:

import { useParams } from 'react-router-dom';

const User = () => {
  const { id } = useParams();
  return 
User ID: {id}
;
};

const App = () => {
  return (
    } />
      
  );
};

export default App;

5. Protected Routes

To implement protected routes, you can create a custom PrivateRoute component:

import { Navigate, Outlet } from 'react-router-dom';

const useAuth = () => {
  const user = { loggedIn: true }; // Replace with actual auth logic
  return user && user.loggedIn;
};

const PrivateRoute = () => {
  const isAuth = useAuth();
  return isAuth ?  : ;
};

const App = () => {
  return (
    } />
        }>
          } />
        
      
  );
};

export default App;

6. Programmatic Navigation

Sometimes, you may want to navigate programmatically, like after a form submission. Use the useNavigate hook in React Router v6:

import { useNavigate } from 'react-router-dom';

const Login = () => {
  const navigate = useNavigate();

  const handleLogin = () => {
    // Login logic here...
    navigate('/dashboard');
  };

  return (
    

      
Login
      Login
    
  );
};

export default Login;

7. 404 Pages

Handle 404 (Not Found) errors by creating a catch-all route:

const NotFound = () => 
404 - Page Not Found
;

const App = () => {
  return (
    } />
        } />
        } />
      
  );
};

export default App;

8. Performance Considerations

For large applications, lazy loading routes can improve performance. Here’s how to implement lazy loading with React.lazy() and Suspense:

import React, { Suspense, lazy } from 'react';
import { BrowserRouter as Router, Routes, Route } from 'react-router-dom';

const Home = lazy(() => import('./Home'));
const About = lazy(() => import('./About'));

const App = () => {
  return (
    Loading...}>
        } />
          } />
        
  );
};

export default App;