JAVASCRIPT
Debounce a Value with the useDebounce Hook
Learn to create a useDebounce React hook to delay state updates, perfect for optimizing search inputs and preventing excessive re-renders or API calls.
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);
useEffect(() => {
if (debouncedSearchTerm) {
console.log('Fetching data for:', debouncedSearchTerm);
// Perform API call or search logic here
}
}, [debouncedSearchTerm]);
return (
<input
type="text"
placeholder="Search..."
value={searchTerm}
onChange={(e) => setSearchTerm(e.target.value)}
/>
);
}
*/
How it works: This useDebounce hook takes a `value` and a `delay` as input. It maintains an internal `debouncedValue` state. Whenever the `value` changes, a `setTimeout` is set. If the `value` changes again before the `delay` expires, the previous `setTimeout` is cleared and a new one is set. This ensures the `debouncedValue` is only updated after the specified `delay` has passed without any new changes to the original `value`, effectively "debouncing" updates.