53 lines
1.3 KiB
Markdown
53 lines
1.3 KiB
Markdown
---
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title: useFetch
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tags: hooks,effect,state,intermediate
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firstSeen: 2019-08-21T14:23:57+03:00
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lastUpdated: 2021-01-07T23:57:13+02:00
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---
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Implements `fetch()` in a declarative manner.
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- Create a custom hook that takes a `url` and `options`.
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- Use the `useState()` hook to initialize the `response` and `error` state variables.
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- Use the `useEffect()` hook to asynchronously call `fetch()` and update the state variables accordingly.
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- Return an object containing the `response` and `error` state variables.
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```jsx
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const useFetch = (url, options) => {
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const [response, setResponse] = React.useState(null);
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const [error, setError] = React.useState(null);
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React.useEffect(() => {
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const fetchData = async () => {
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try {
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const res = await fetch(url, options);
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const json = await res.json();
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setResponse(json);
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} catch (error) {
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setError(error);
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}
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};
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fetchData();
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}, []);
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return { response, error };
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};
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```
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```jsx
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const ImageFetch = props => {
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const res = useFetch('https://dog.ceo/api/breeds/image/random', {});
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if (!res.response) {
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return <div>Loading...</div>;
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}
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const imageUrl = res.response.message;
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return (
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<div>
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<img src={imageUrl} alt="avatar" width={400} height="auto" />
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</div>
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);
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};
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ReactDOM.render(<ImageFetch />, document.getElementById('root'));
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```
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