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REGEXP help need to render 404 path

I'm trying to use REGEXP to help render a 404 page in a react app using the path. I cannot figure it out.
This is the REGEXP I want; I want to match IF:
The entire path is !== '/' && does not contain the word 'article'.
EDIT: Including code for clarification:
<Switch location={location} key={location.pathname}>
<Route path={["/commentisfree/article/:id", "/commentisfree"]}>
<Opinion />
</Route>
<Route path={["/sport/article/:id", "/sport"]}>
<Sport />
</Route>
<Route path={["/culture/article/:id", "/culture"]}>
<Culture />
</Route>
<Route path={["/lifestyle/article/:id", "/lifestyle"]}>
<Lifestyle />
</Route>
<Route path={["/signup", "/login"]}>
<Account />
</Route>
<Route path={["search/:search", "/search"]}>
<Search />
</Route>
<Route path={/REGEXP[if path !== "/" && path does NOT include the word "article"]/} component={ErrorDefault} />
<Route path={["/article/:id", "/"]}>
<Home />
</Route>
</Switch>
At the bottom you'll see I've had to put the 404 component just above my index route because the 404 is never hit if I use a catch all route, it simply navigates to the index route but maintains the incorrect URL.
For example, entering http://localhost:3000/mistake takes me to the index route. I don't want this as I rely on the urls to render modular components and it doesn't work if the path is incorrect.
So i need to force any non declared paths to a 404 page where i can display a message and a link back to the home page.

Are you using React router?
If so, you could use a catch-all route at the end of the route list, which will render a 404 page, like here: https://reactrouter.com/web/example/no-match
Edited: added link to React router documentation

The following function uses Regular Expression
const checkRegex = (urlString) => {
return (
new RegExp("/").test(urlString) && new RegExp("article").test(urlString)
);
};
You can also use the includes function for this
const checkRegex = (urlString) => {
return (
urlString.includes('article') && urlString.includes('/')
);
};

React Router: <Redirect push> doesn't update browser url

I'm learning React making a small single page app. Just added react-router-dom today and building it out to do routes and private routes. All is well except for one thing: When the user enters a malformed url in the browser bar, the user should be rerouted to the index (WORKS!), but the browser url bar is not updated on this redirect. Oddly enough, when I hit a private route while not authorized, the redirect DOES update the url bar. What am I missing?
router.js:
const PrivateRoute = ({auth: authenticated, component: Component, ...rest}) => (
<Route {...rest} render={(props) => (
authenticated === true
? <Component {...props} />
: <Redirect to='/login/'/>
)}/>
);
export default function Router() {
const auth = useSelector(isAuthenticated);
return (
<Switch>
<PrivateRoute auth={"auth"} path={"/dashboard/"} component={DashboardContainer}/>
<Route path={"/about/"} component={AboutContainer}/>
<Route path={"/login/"} component={LoginContainer}/>
<Route path={"/terms/"} component={TermsContainer}/>
<Route path={"/"} component={IndexContainer}/>
<Redirect push to={"/"}/>
</Switch>
);
}

I believe your issue is a result of not specifying that the paths should be exact matches, therefore any route will match with your route that is specified as:
<Route path={"/"} component={IndexContainer}/>
Try adding the exact prop to all of your routes (except for your redirect), and you should properly get redirected to the home page with the correct URL.
More details on the exact prop here: React : difference between <Route exact path="/" /> and <Route path="/" />

Multiple path names for a same component in Reach Router

I am using the same component for three different routes:
<Router>
<Home path="/" />
<Home path="/home" />
</Router>
Is there anyway to combine it, to be like:
<Router>
<Home path=["/home", "/"] />
</Router>

For Reach Router: (https://reach.tech/router/example/)
With the exact sample shown, the only way I can see how to do this(on a single line) is with a wildcard.
To find a way to reproduce this without side effects, we would need to see the entire nav menu.
<Router>
<Home path="/*" />
<Chicken path="chicken">
</Router>
...
const Home = props => {
let urlPath = props["*"]
// URL: "/home"
// urlPath === "home"
// URL/: "/"
// urlPath ===""
}
You could continue with other paths below Home and the router would allow them to process.
Check out the the example using a wildcard and reach router on codesandbox, I wrote!
Note: This is a catch-all, but without parsing a parameter is the only single line solution I saw.
Some DrawBacks include Home rendering instead of '404', etc.
//This could be resolved with an if statement in your render
//It will not produce the intended URL either for /home, and I have not looked into that since it is not part of the question.. but if it matched props[*] I'm sure you could redirect or something.
You can read more about the Route Component for Reach Router.
https://reach.tech/router/api/RouteComponent

I wasn't happy with the wildcard solution from the documentation and #cullen-bond because I had to map many other paths and came up with this solution:
<Router>
{["/home", "/", "/other", "/a-lot-more"].map(page => <Home path={page} />)}
</Router>
Example: https://codesandbox.io/s/reach-router-starter-v1-forked-6f44c?file=/src/index.js

Depending on the situation you're dealing with, <Redirect /> could also make the work.
<Router>
<Redirect from="/" path="/home" noThrow />
<Home path="/home" />
</Router>

You can use a single component for mutiple paths, by using a array of routes.
code example :
import sampleComponent from './sampleComponent'; // single component for mutiple routes
<Router>
<Switch>
{["/pathname_1", "/pathname_2", "/pathname_3", "/pathname_4", "/pathname_5", "/pathname_6"].map(pathname => (<Route exact path={pathname} component={sampleComponent} />) )}
<Switch>
<Router>

react-router-dom refresh component when route changes

I used same component for different routes. When route changes, I want the component to be rendered.
<Switch>
<Route exact path="/" component={HomePage} />
<Route path="/hotels" component={HotelsPage} />
<Route path="/apartments" component={HotelsPage} />
</Switch>
When I change the route path from /hotels to /apartments, the component HotelsPage doesn't refresh.
What is the cool approach for this?

One of the ways you can get this sorted is by passing the props explicitly like :
<Route path="/hotels" component={props => <HotelsPage {...props} />} />

Firstly you can aggregate the Route into one like
<Switch>
<Route exact path="/" component={HomePage} />
<Route path="/(hotels|apartments)" component={HotelsPage} />
</Switch>
and secondly, your HotelsPage component is rendered both on /hotels, /apartments, it is similar case like path params, whereby the component doesn't mount again on path change, but updates thereby calling componentWillReceiveProps lifecycle function,
What you can do is implement componentWillReceiveProps like
componentWillReceiveProps(nextProps) {
if (nextProps.location.pathname !== this.props.location.pathname) {
console.log("here");
//take action here
}
}
DEMO

I guess just passing useLocation().pathname will resolve issue
useEffect(
() => {
// Your logics
});
}, [useLocation().pathname])

<Switch> component matching null value in react-router-4

I'm trying to migrate to use React Router 4 and having some trouble understanding the logic of the <Switch> component as it's used in the docs to handle a 404 (or unmatched) route.
For my entry JavaScript file, I have the following routes set up.
index.js
<Switch>
<Route path="/login" component={Login} />
<Route path="/forgot-password" component={ForgotPassword} />
<Route path="/email-verification" component={EmailVerification} />
<Route component={App} />
</Switch>
The Login component will check to see if the user is authenticated, and if so, redirect the user to the /dashboard route (via history.replace).
The App component is only accessible when the user is authenticated and it has a similar check to redirect the user to /login if she is not.
In my App component I have more specified routes that I can be sure are only accessible if the user is logged in.
App.js
<Switch>
<Route path="/dashboard" component={Dashboard} />
<Route path="/accounts" component={Account} />
<Authorize permissions={['view-admin']}>
<Route path="/admin" component={Admin} />
</Authorize>
<Route path="/users" component={Users} />
<Route component={NotFound} />
</Switch>
Herein lies my problem. The Authorize component checks against the permissions passed to see if the user has those permissions, if so, it renders the children directly, if not, it returns null from render().
The expected behavior here is that the <Route path="/admin" /> does not render at all when there are insufficient permissions and the <Route component={NotFound} /> component renders.
According to the docs:
A renders the first child that matches. A
with no path always matches.
However, if I go to any route declared after the <Authorize> component, the router is matching to null. This means that, based on the example above, going to /users returns null. Is the expected behavior of react-router to return the first match in a <Switch/> component, even if it's a null value?
How can I provide a "catch-all" route (404) for such a situation without creating a <PrivateRoute> component for each of the many, authenticated routes in App.js? Should a null value really produce a match?

Unfortunately, react-router's Switch component won't work with routes nested inside other components like in your example. If you check the docs for Switch, it says:
All children of a <Switch> should be <Route> or <Redirect> elements.
... so your Authorize component is not actually legal there as a direct child of Switch.
If you have a read through the source code of the Switch component, you'll see that it rather evilly reads the props of each of its children and manually applies react-router's matchPath method on each child's path (or from) prop to determine which one should be rendered.
So, what's happening in your case is Switch iterates through its children until it gets to your Authorize component. It then looks at that component's props, finding neither a path or from prop, and calls matchPath on an undefined path. As you note yourself, "a <Route> with no path always matches", so matchPath returns true, and Switch renders your Authorize component (ignoring any subsequent Routes or Redirects, since it believes it found a match). The nested '/admin' route inside your Authorize component doesn't match the current path however, so you get a null result back from the render.
I'm facing a similar situation at work. My plan to work around it is to replace react-router's Switch in my routing code with a custom component which iterates through its children, manually rendering each one in turn, and returning the result of the first one that returns something other than null. I'll update this answer when I've given it a shot.
Edit: Well, that didn't work. I couldn't work out a supported way to manually invoke "render" on the children. Sorry I couldn't give you a workaround to Switch's limitations.

In case anyone reads this in >= 2019, one way to deal with this behaviour is to simply wrap the Route-component like so:
import React from 'react'
import { Route } from 'react-router-dom'
type Props = {
permissions: string[]
componentWhenNotAuthorized?: React.ElementType
}
const AuthorizedRoute: React.FunctionComponent<Props> = ({
permissions,
componentWhenNotAuthorized: ComponentWhenNotAuthorized,
...rest
}) => {
const isAuthorized = someFancyAuthorizationLogic(permissions)
return isAuthorized
? <Route {...rest} />
: ComponentWhenNotAuthorized
? <ComponentWhenNotAuthorized {...rest} />
: null
}
export default AuthorizedRoute
Then, simply use it as such:
import React from 'react'
import { Route, Switch } from 'react-router-dom'
import AuthorizedRoute from 'some/path/AuthorizedRoute'
import Account from 'some/path/Account'
import Admin from 'some/path/Admin'
import Dashboard from 'some/path/Dashboard'
import NotFound from 'some/path/NotFound'
import Users from 'some/path/Users'
const AppRouter: React.FunctionComponent = () => (
<Switch>
<Route
component={Account}
path='/accounts'
/>
<AuthorizedRoute
component={Admin}
componentWhenNotAuthorized={NotFound}
path='/admin'
permissions={['view-admin']}
/>
<Route
component={Dashboard}
path='/dashboard'
/>
<Route
component={Users}
path='/users'
/>
<Route
component={NotFound}
/>
</Switch>
)
export default AppRouter

Similar idea to what Robert said, here's how I did it
class NullComponent extends React.Component {
shouldComponentBeRenderedByRoute() {
return false;
}
render() {
return null;
}
}
class CustomSwitch extends React.Component {
render() {
return (
// React.Children.map returns components even for null, which
const children = React.Children.toArray(this.props.children).map(child => {
const { render, shouldComponentBeRenderedByRoute } = child.type.prototype;
if (shouldComponentBeRenderedByRoute && !shouldComponentBeRenderedByRoute.call(child)) {
return null;
}
if (shouldComponentBeRenderedByRoute) {
return render.call(child);
}
return child;
});
return <Switch>{children}</Switch>;
);
}
}
then use it just do
<CustomSwitch>
<Route path... />
<NullComponent />
<Route path... />
</CustomSwitch>
here, a component without shouldComponentBeRenderedByRoute function is assumed to be a valid Route component from react-router, but you can add more condition (maybe use path props) to check if it's a valid Route