How to parse a query string in React Router

Question

Hello I´m using react router and I need to pass some querystring parameters

tried with

<Route path="/result/:type?/?filter=:filter?" exact strict component={Result}/>

I was expecting that to catch urls like

/result
/result/animals
/result/cars
/result/animals?filter=cats,dogs
/result/cars?filter=sedan,truck

what´s the right way to do it?

Answer 1

For url parameters, like /animals and /cars, you can use the colon syntax /:type

But for query parameters, like ?filter=something, you need to parse the query string.

According to react-router docs:

React Router does not have any opinions about how your parse URL query strings. Some applications use simple key=value query strings, but others embed arrays and objects in the query string. So it's up to you to parse the search string yourself.

In modern browsers that support the URL API , you can instantiate a URLSearchParams object from location.search and use that.

In browsers that do not support the URL API (read: IE) you can use a 3rd party library such as query-string.

For example, in your component you will have location as a prop from the parent Route (or you can get it from withRouter), you can then use location.search to parse the query string like this:

function Parent({location}) {
  let params = new URLSearchParams(location.search);

  return <Child name={params.get("filter")} />;
}

For more info:

• React Router Docs - Query Parameters

• Example CodeSandbox

Answer 2

Older versions of React Router offered this functionality but ultimately they decided it was too cumbersome to handle the variation across browsers.

As of the current version (v4), you need to use a library, such as query-string.

One more option to consider: if you know your target browsers support the URLSearchParams API, you can use that instead.

Install package:

yarn add query-string

Usage:

import queryString from 'query-string'

...

componentDidMount() {
  const values = queryString.parse(this.props.location.search)
}