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Conditional display of component based on Route matching

I am looking to conditionally render a component based on the route (using React Router), and the component should return null if it matches any path pre-defined in an array or some sort of similar data structure, where I do not have to be reliant on a <Switch>/<Route> setup. Currently here is what I have but it is clearly inefficient and not robust at all.
const Component = (props) => {
const path = props.location.pathname;
const paths_to_hide = ["/path/to/something", "/path/to/A", "/path/to/B"];
if (paths_to_hide.indexOf(path) != -1) return null;
return (
<div>test</div>
);
}
For example, if I want to match the following paths:
/path/to/something
/path/to/something/<any path that follows after this>
/path/<random string>/fixed
/newPath/<random string>
Note that this list is not just limited to 4 items, which is why I'm trying to stray away from having inline <Route> matching as I'm looking for a more scalable approach which I can save in a config file and have imported as an array or some similar data structure.
Currently my implementation will only be able to identify the first item, and there is no way to match the subsequent items, using the indexOf() function. What would be the best way to accomplish this? Any help is appreciated, thank you!

So upon reading the React Router docs further, I found this. This is definitely the most ideal solution and I overlooked this initially.
const Component = (props) => {
const path = props.location.pathname;
const paths_to_hide = ["/path/to/something", "/path/to/A", "/path/to/B"];
return (
<Switch>
<Route path={paths_to_hide}>
</Route>
<Route>
<div>test</div>
</Route>
</Switch>
);
}
So now I can create complex paths and don't have to loop through an array to match them, as it's taken care of by the Route component, and this is ideal because now I can import this array from a config file instead.

How to create routes with dynamic params in gatsbyjs [duplicate]

I have setup gatsby project using this link. It is working correctly.
Now I know how to create route by defining the component inside the pages folder. But now I have a new challenge I need to create one dynamic route so that I can pass my id in it (Just like reactjs).
<Route path: "/path/:id"/>
How do I do that in gatsby?

You have to explicitly tell gatsby that a path should be dynamic. From the docs:
// gatsby-node.js
// Implement the Gatsby API “onCreatePage”. This is
// called after every page is created.
exports.onCreatePage = async ({ page, actions }) => {
const { createPage } = actions
// page.matchPath is a special key that's used for matching pages
// only on the client.
if (page.path.match(/^\/app/)) {
page.matchPath = "/app/*"
// Update the page.
createPage(page)
}
}
and then you can use dynamic routing in src/pages/app.js
import { Router } from "#reach/router"
const SomeSubPage = props => {
return <div>Hi from SubPage with id: {props.id}</div>
}
const App = () => (
<Layout>
<Link to="/app/1">First item</Link>{" "}
<Link to="/app/2">Second item</Link>{" "}
<Router>
// ...dynamic routes here
<SomeSubPage path="/app/:id" />
</Router>
</Layout>
)
export default App
Everything that goes to /app/* will be handled dynamically now. You should find your id as usual in the props.
Have a look at their authentication example https://github.com/gatsbyjs/gatsby/tree/master/examples/simple-auth

You can use square brackets ([ ]) in the file path to mark any dynamic segments of the URL. For example, in order to edit a user, you might want a route like /user/:id to fetch the data for whatever id is passed into the URL.
src/pages/users/[id].js will generate a route like /users/:id
src/pages/users/[id]/group/[groupId].js will generate a route like /users/:id/group/:groupId
Reference: https://www.gatsbyjs.com/docs/reference/routing/file-system-route-api#creating-client-only-routes

You can use gatsby-plugin-create-client-paths. It uses matchPath. For more info check
https://www.gatsbyjs.org/docs/gatsby-internals-terminology/#matchpath
https://www.gatsbyjs.org/packages/gatsby-plugin-create-client-paths/

This answer is Super late, but for anyone in the future who is faced with this problem, I have a simpler solution.
In Gatsby terms it's called a Splat Route.
For examples, If you want some page "domain.com/profile/[id]", where id can be any number, which will be used to display different data inside the website, you should name your page as [...id].
Now inside the page you can access this id as
const ProfilePage = (props) => <div>This page is for id number {props.params.id}</div>
Note: Don't miss the 3 dots, that is what signifies a splat route in gatsby.

how to check if url param entered exist in location.pathname via React

Well, I try to understand legacy code with React routes onboard.
I have an url like
/home/reports/some_report_numbers
when user changes the ulr like that:
/home/reports/some_report_numb
I want to check if "some_report_numb" exists in props, in this.props.location.pathname. If exists - fine, go that way, otherwise go another way.
Maybe it is a wrong approach at all? Well, when the report is shown and user just deletes some letters in url I need to redirect to /home/ page. To do that I need somehow to check if that report with that numbers exists at all.
Maybe it could be done via
<Route name={SomeRouteName} path='reports/:reportId' component={HomePage} />

According to the documentation of react-router-dom
Link: https://reacttraining.com/react-router/web/example/url-params
match become an object that can be used in your component. Like explain in the documentation, you have access to match object with the following steps:
Route component as this.props.match
Route render as ({ match }) => ()
Route children as ({ match }) => ()
withRouter as this.props.match
matchPath as the return value
For example, if you have the following route:
<Route path="/reports/:reportId" component={HomePage} />
In your component, you can access to this with: this.props.match because it's an object and inside it, you will have what you want.
After that, you could check what params you have in your URL.
Now, if you want to redirect the user, you can use <Redirect to={'/your/path'} />

match route that has param doesn't work with react-router v4

<Route path='/change-password/?resetToken=(:token)' component={()=><h1>testing</h1>} />
Above route don't render when I hit the url below?
http://localhost:3000/change-password/?resetToken=123
I also tried path='/change-password/?resetToken=:token'

So the main problem seems to be with the question mark in the path. But first you need to write :token instead of (:token), here is an example format of path with params on github docs of the react-router.
I followed this github post about no way to set reserved characters in the path name, but it didn't lead me to anything. One way you could solve the problem is to define your route like /change-password and then in the actual component do this.props.location.search.split("=")[1] to get the value of the token from the search query. Here is an example:
class ChangePassword extends React.Component {
componentDidMount() {
// get the token, check if it exists and do smth with it if it does
console.log(this.props.location.search.split("=")[1]);
}
render() {
return (<h1>Change password</h1>);
};
}
const App = () => (
<Router>
<div>
<Route path='/change-password' component={ChangePassword} />
<Route path='/home' component={ChangePassword} />
</div>
</Router>
);
It seems that react-router doesn't handle ? (or other reserved characters, haven't tested) in the path name, or I am seriously missing out something here and there is some magic option that makes it work :) I didn't find one but I made a working example with the code I provided on codesanbdbox with your path in the Route.

Passing optional parameter in react router

Say I have http://www.example.com/page/#/search routed like this:
<Router history={hashHistory}>
<Route path='/search/' component={SearchPage} />
</Router>
And when the user does a search on the page using the provided name and age search boxes (either can be left out, or both can be filled), I want it to redirect to:
http://www.example.com/page/#/search/?name=whatever%20name&age=15
Which will display the results for this particular search. This would also allow linking directly to search results.
Now inside my SearchPage component, how can I check if ?name= or ?age= or any other search parameters have been provided?

In your container say SearchPage you can access queryParams like this
this.props.location.query.yourKey.
As an example
class SearchPage extends React.Component{
componentWillMount(){
const {name, age} = this.props.location.query;
//here you can give default values if they are empty
//do whatever you want
}
}

There are two ways of achieving this either you can use params or query values.
By params:
In the route first define your optional parameters like this:
<Router history={hashHistory}>
<Route path='/search(/:name)(/:age)' component={SearchPage} />
</Router>
Include componentWillReceiveProps() method in your component it will get triggered whenever component receive any new props, like this:
componentWillReceiveProps(newProps){
console.log(newProps.params.name, newProps.params.age);
// here you can check the props value
}
In the component you can check the value by this.props.params.name or age.
By query parameter:
no change is required in the route, just pass the values in url and check like this:
this.props.location.name or age.
Read this article for about params and query values in react: https://www.themarketingtechnologist.co/react-router-an-introduction/

With the latest update "location.query" is not exposed, we have to use "location.search" to get the optional unnamed parameters. However, The named optional parameter still can be read through "props.match.params"
Route :
<Route path="/partner/list-space/step-1/:_id?" component={ListSpace}/>
Fetching the named optional parameter "id" in component or hooks
let id = props.match.params._id;
To fetch the unnamed optional parameter such as "space" from the url.
http://localhost:3000/partner/list-space/step-1/123?space=new&guests=4
We have to use "querystringify".
import qs from "querystringify";
const qsParams = qs.parse(props.location.search);
Results :
props.match.params._id => "123"
qsParams.space => new
qsParams.guests => 4