useHooks(🐠)

Easy to understand React Hook recipes by ui.dev

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Hooks are a feature in React that allow you use state and other React features without writing classes. This website provides easy to understand code examples to help you learn how hooks work and inspire you to take advantage of them in your next project.

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useRouter

If you use React Router you might have noticed they recently added a number of useful hooks, specifically useParams, useLocation, useHistory, and use useRouteMatch. But let's see if we can make it even simpler by wrapping them up into a single useRouter hook that exposes just the data and methods we need. In this recipe we show how easy it is to compose multiple hooks and combine their returned state into a single object. It makes a lot of sense for libraries like React Router to offer a selection of low-level hooks, as using only the hook you need can minimize unnecessary re-renders. That said, sometimes you want a simpler developer experience and custom hooks make that easy.

import { useMemo } from "react";
import {
  useParams,
  useLocation,
  useHistory,
  useRouteMatch,
} from "react-router-dom";
import queryString from "query-string";

// Usage
function MyComponent() {
  // Get the router object
  const router = useRouter();

  // Get value from query string (?postId=123) or route param (/:postId)
  console.log(router.query.postId);

  // Get current pathname
  console.log(router.pathname);

  // Navigate with router.push()
  return <button onClick={(e) => router.push("/about")}>About</button>;
}

// Hook
export function useRouter() {
  const params = useParams();
  const location = useLocation();
  const history = useHistory();
  const match = useRouteMatch();

  // Return our custom router object
  // Memoize so that a new object is only returned if something changes
  return useMemo(() => {
    return {
      // For convenience add push(), replace(), pathname at top level
      push: history.push,
      replace: history.replace,
      pathname: location.pathname,
      // Merge params and parsed query string into single "query" object
      // so that they can be used interchangeably.
      // Example: /:topic?sort=popular -> { topic: "react", sort: "popular" }
      query: {
        ...queryString.parse(location.search), // Convert string to object
        ...params,
      },
      // Include match, location, history objects so we have
      // access to extra React Router functionality if needed.
      match,
      location,
      history,
    };
  }, [params, match, location, history]);
}
October 21, 2019
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