JAVASCRIPT
Debounce State Changes with `useDebounce`
Create a custom React hook, `useDebounce`, to delay updating a state value, optimizing performance for fast-changing inputs like search fields and resize events.
import { useState, useEffect } from 'react';
function useDebounce(value, delay) {
const [debouncedValue, setDebouncedValue] = useState(value);
useEffect(() => {
const handler = setTimeout(() => {
setDebouncedValue(value);
}, delay);
return () => {
clearTimeout(handler);
};
}, [value, delay]);
return debouncedValue;
}
// Example Usage:
/*
function SearchInput() {
const [searchTerm, setSearchTerm] = useState('');
const debouncedSearchTerm = useDebounce(searchTerm, 500); // Debounce for 500ms
useEffect(() => {
if (debouncedSearchTerm) {
console.log('Searching for:', debouncedSearchTerm);
// Perform API call or heavy computation here
}
}, [debouncedSearchTerm]);
return (
<input
type="text"
placeholder="Search..."
value={searchTerm}
onChange={(e) => setSearchTerm(e.target.value)}
/>
);
}
*/
How it works: The `useDebounce` hook takes a `value` and a `delay` as arguments. It maintains an internal `debouncedValue` state. Whenever the `value` changes, a `setTimeout` is set to update `debouncedValue` after the specified `delay`. If the `value` changes again before the timeout expires, the previous timeout is cleared, and a new one is set. This ensures that the `debouncedValue` only updates after a period of inactivity, which is perfect for optimizing expensive operations like API calls triggered by user input.