30 lines
752 B
Markdown
30 lines
752 B
Markdown
---
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title: useComponentDidMount
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tags: hooks,effect,beginner
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firstSeen: 2020-01-03T15:56:54+02:00
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lastUpdated: 2020-11-16T14:17:53+02:00
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---
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Executes a callback immediately after a component is mounted.
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- Use `useEffect()` with an empty array as the second argument to execute the provided callback only once when the component is mounted.
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- Behaves like the `componentDidMount()` lifecycle method of class components.
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```jsx
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const useComponentDidMount = onMountHandler => {
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React.useEffect(() => {
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onMountHandler();
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}, []);
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};
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```
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```jsx
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const Mounter = () => {
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useComponentDidMount(() => console.log('Component did mount'));
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return <div>Check the console!</div>;
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};
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ReactDOM.render(<Mounter />, document.getElementById('root'));
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```
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