React useFetch hook
Implements fetch()
in a declarative manner.
- Create a custom hook that takes a
url
andoptions
. - Use the
useState()
hook to initialize theresponse
,error
andabort
state variables. - Use the
useEffect()
hook to asynchronously callfetch()
and update the state variables accordingly. - Create and use an
AbortController
to allow aborting the request. Use it to cancel the request when the component unmounts. - Return an object containing the
response
,error
andabort
state variables.
const useFetch = (url, options) => {
const [response, setResponse] = React.useState(null);
const [error, setError] = React.useState(null);
const [abort, setAbort] = React.useState(() => {});
React.useEffect(() => {
const fetchData = async () => {
try {
const abortController = new AbortController();
const signal = abortController.signal;
setAbort(abortController.abort);
const res = await fetch(url, {...options, signal});
const json = await res.json();
setResponse(json);
} catch (error) {
setError(error);
}
};
fetchData();
return () => {
abort();
}
}, []);
return { response, error, abort };
};
const ImageFetch = props => {
const res = useFetch('https://dog.ceo/api/breeds/image/random', {});
if (!res.response) {
return <div>Loading...</div>;
}
const imageUrl = res.response.message;
return (
<div>
<img src={imageUrl} alt="avatar" width={400} height="auto" />
</div>
);
};
ReactDOM.render(<ImageFetch />, document.getElementById('root'));