Develop Reference

Why are my React components rendering in all routes?

This is the my App() function in App.js, the comps :"Sidebar, Feed and Widgets" keeps rendering in route ="/" and also ="/login" as well, in addition to that "Login" comp didn't even render in route ="/login".
<Router>
<div className="app">
<Switch>
<Route path="/">
<Sidebar />
<Feed />
<Widgets />
</Route>
<Route path="/login">
<Login />
</Route>
</Switch>
</div>
</Router>

If you are using the latest version of react-router-dom, you must change the Switch to Routes
import { BrowserRouter as Router, Routes, Route } from 'react-router-dom'
import { Sidebar, Feed, Widgets } from '...'
const Home = () => {
return (
<Sidebar />
<Feed />
<Widgets />
)
}
const App = () => {
return (
<Router>
<div className="app">
<Routes>
<Route path="/" element={<Home />} />
<Route path="/login" element={<Login />} />
</Routes>
</div>
</Router>
)
}

You need to add exact with "/'" route.
In your case when you are not adding exact, React router will match '/login' path with the first path '/' and will render accordingly without checking next routes. By adding exact, first '/' will not match and it will match with second route '/login'.
<Router>
<div className="app">
<Switch>
<Route path="/" exact>
<Sidebar />
<Feed />
<Widgets />
</Route>
<Route path="/login">
<Login />
</Route>
</Switch>
</div>
</Router>
For more information, you can also refer this similar question: React : difference between <Route exact path="/" /> and <Route path="/" />

The Switch component exclusively matches and renders routes, so only 1 route can ever be matched. You've an issue with the order of your routes though, so only the "/" path matches since it's earlier and is rendered. The route for "/login" can never be reached, as-is.
In other words, this means is that when the path is "/login" that "/" still matches it and is the route rendered. In react-router-dom v5 think of the path props as a "path prefix".
In the Switch component, path order and specificity matter! You should order the paths from more specific to less specific. This allows more specific paths like "/login" to be matched before trying the less specific paths.
<Router>
<div className="app">
<Switch>
<Route path="/login">
<Login />
</Route>
<Route path="/">
<Sidebar />
<Feed />
<Widgets />
</Route>
</Switch>
</div>
</Router>

React router always display at the bottom the Error page

I'm having a problem regarding using of error page in my react app. The 404 page always shows at the bottom of every page that I render. I'm new to react. I hope someone can help me.
This is my App.js
import {BrowserRouter as Router,Switch,Route} from 'react-router-dom';
import Login from './components/auth/Login';
import Register from './components/auth/Register';
import ErrorPage from './components/ErrorPage';
import Order from './components/Order';
import Navbar from './components/partials/Navbar';
import Footer from './components/partials/Footer';
import Shop from './components/Shop';
import ItemDetails from './components/ItemDetails';
import Cart from './components/Cart';
import Customize from './components/Customize';
const App = () => {
return (
<>
<Router>
<Switch>
<Route exact path='/login'>
<Login />
</Route>
<Route exact path='/register'>
<Register />
</Route>
<div>
<Navbar />
<Route exact path='/'>
<Shop />
</Route>
<Route exact path='/order'>
<Order />
</Route>
<Route exact path='/item/details'>
<ItemDetails />
</Route>
<Route exact path='/cart'>
<Cart />
</Route>
<Route exact path='/customize'>
<Customize />
</Route>
<Route component={ErrorPage} />
</div>
</Switch>
</Router>
<Footer />
</>
);
}
export default App;
I searched about handling error page in react and I see that the order of routes is important but I don't get why I'm still getting the error page even it's in the bottom. Thank you guys.

That's because the switch component returns the first child at the root that meets the path condition. If the path condition doesn't exist it's evaluated as true. In your case you have 3 child Login, Register and the div which will always be evaluated to true. So just move all routes to the root of your switch:
<Router>
<Switch>
<Route exact path='/login'>
<Login />
</Route>
<Route exact path='/register'>
<Register />
</Route>
<div>
<Navbar />
<Switch>
<Route exact path='/'>
<Shop />
</Route>
<Route exact path='/order'>
<Order />
</Route>
<Route exact path='/item/details'>
<ItemDetails />
</Route>
<Route exact path='/cart'>
<Cart />
</Route>
<Route exact path='/customize'>
<Customize />
</Route>
<Route component={ErrorPage} />
</Switch>
</div>
</Switch>
</Router>

Hide specific components for a route using React Router

In my code, I want Header & Footer components to be rendered in all routes except '/login'so how to do that? How to hide component on a specific route?
const AppRouter = () => {
return (
<BrowserRouter>
<div>
<Header />
<Switch>
<Route path="/login" component={Login} /> {/* I wanna render this route without Header & Footer */}
<Route path="/" component={Home} exact />
<Route path="/product" component={ProductOverview} />
<Route path="/profile" component={Profile} />
<Route component={NotFound} />
</Switch>
<Footer />
</div>
</BrowserRouter>
);
};

How to perform dynamic component rendering using react router v4?

I have an application with a Login page followed by a Dashboard page. The routes that I've defined in the index.js are like this:
<Router>
<div>
<Route exact path="/" component={Login}/>
<Route path="/dashboard" component={Dashboard} />
</div>
</Router>
Dashboard.js:
return (
<div>
<Header/>
<Footer/>
<Switch>
<Route path="/dashboard/content1" component={content1} />
<Route path="/dashboard/content2" component={content2} />
</Switch>
</div>
);
The Dashboard component is rendering 3 of its child components. Header, Footer and Content1. I want the Dashboard component to render Content1 by default (i.e. when the url is /dashboard) and also when the url is /dashboard/content1, and should render content2 when the url is /dashboard/content2. Header & Footer components should remain. Please suggest the configuration for the Dashboard component to achieve the same.

In React-router v4 you provide Routes within the component, so you can write your Routes as follows
<Router>
<div>
<Route exact path="/" component={Login}/>
<Route path="/dashboard" component={Dashboard} />
</div>
</Router>
and then in the Dashboard Component render method
render() {
return (
<div>
{/* other content */}
<Switch>
<Route exact path="/dashboard" component={content1} />
<Route path="/dashboard/content1" component={content1} />
<Route path="/dashboard/content2" component={content2} />
</Switch>
</div>
)
}

As a variant of an answer to your post before you have edited it, you can do it (nesting) like this:
<Router>
<Header/>
<Content1/>
<Footer/>
<Switch>
<Route exact path="/" component={Login}/>
<Route exact path="/dashboard" component={Dashboard} />
<Route exact path="/dashboard/content1" component={content1} />
<Route exact path="/dashboard/content2" component={content2} />
</Switch>
</Router>

React-Router's Switch component renders the first thing that matches,
so if you put a route without a path last, it will render that if no other routes match, essentially treating it as a default. Like so:
return (
<div>
<Header/>
<Footer/>
<Switch>
<Route path="/dashboard/content2" exact component={Content2} />
<Route component={Content1} />
</Switch>
</div>
);
I have found that rendering a component instead of a Route also works, although I dont know if it's officially supported.
return (
<div>
<Header/>
<Footer/>
<Switch>
<Route path="/dashboard/content2" exact component={Content2} />
<Content1 />
</Switch>
</div>
);

Default component in nested routes in React Router

In React Router I have a nested Route
<Route path='about' component={{main: About, header: Header}}>
<Route path='team' component={Team} />
</Route>
So now it shows Team when I go to /about/team.
But how do I set which Component to be seen when I visit /about?
I have tried
<Route path='about' component={{main: About, header: Header}}>
<IndexRoute component={AboutIndex} />
<Route path='team' component={Team} />
</Route>
and
<Route path='about' component={{main: About, header: Header}}>
<Route path='/' component={AboutIndex} />
<Route path='team' component={Team} />
</Route>
but it doesn't work.
My About component looks like this
class About extends React.Component {
render () {
return (
<div>
<div className='row'>
<div className='col-md-9'>
{this.props.children}
</div>
<div className='col-md-3'>
<ul className='nav nav-pills nav-stacked'>
<li className='nav-item'><IndexLink className='nav-link' to='/about' activeClassName='active'>About</IndexLink></li>
<li className='nav-item'><Link className='nav-link' to='/about/team'>Team</Link></li>
</ul>
</div>
</div>
</div>
);
}
}

REACT ROUTER 4 UPDATE
The default route is the one without a path.
import BrowserRouter from 'react-router-dom/BrowserRouter';
import Switch from 'react-router-dom/Switch';
import Route from 'react-router-dom/Route';
<BrowserRouter>
<Switch>
<Route exact path='/about' component={AboutIndex} />
<Route component={AboutIndex} /> // <--- don't add a path for a default route
</Switch>
</BrowserRouter>
If you don't need this object {main: About, header: Header} in your component, then just put AboutIndex in the component attribute. That should work
<Router history={browserHistory}>
<Route path='about' component={AboutIndex}>
<IndexRoute component={AboutIndex} />
<Route path='team' component={Team} />
</Route>
</Router>
If you still need main and header components, just add them in as either parent, child, or sibling components depending on your needs

React Router v6
The route has an attribute index which is used to define the index route as per the docs.
<Route index element={<DefaultPage />} />

Another way to do I found is to use the Navigate component of the react-router-dom package with the index attribute. After the a user navigates to the support route, it will default to the about page in the following example.
<Route path="support/*" element={<Support />}>
<Route index element={<Navigate to="about" replace />} />
<Route path="about" element={<About />} />
<Route path="contact" element={<Contact/>} />
</Route>