JAVASCRIPT
Custom useDebounce Hook for Input Delay
Learn to create a `useDebounce` custom React hook to delay state updates, optimizing performance for search inputs or frequently triggered 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 SearchBar() {
// const [searchTerm, setSearchTerm] = useState('');
// const debouncedSearchTerm = useDebounce(searchTerm, 500); // 500ms delay
// useEffect(() => {
// if (debouncedSearchTerm) {
// console.log('Fetching data 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: This custom `useDebounce` hook delays updating a value until a specified `delay` time has passed without further changes to the input `value`. It uses `useState` to hold the debounced value and `useEffect` with `setTimeout` and `clearTimeout` to manage the delay. This is extremely useful for optimizing performance in scenarios like search bars, where you want to avoid making API calls on every keystroke.