30秒学会 React 片段 – React useDebounce hook

Debounces the given value.

• Create a custom hook that takes a value and a delay.
• Use the useState() hook to store the debounced value.
• Use the useEffect() hook to update the debounced value every time value is updated.
• Use setTimeout() to create a timeout that delays invoking the setter of the previous state variable by delay ms.
• Use clearTimeout() to clean up when dismounting the component.
• This is particularly useful when dealing with user input.

代码实现

const useDebounce = (value, delay) => {
  const [debouncedValue, setDebouncedValue] = React.useState(value);

  React.useEffect(() => {
    const handler = setTimeout(() => {
      setDebouncedValue(value);
    }, delay);

    return () => {
      clearTimeout(handler);
    };
  }, [value]);

  return debouncedValue;
};

使用样例

const Counter = () => {
  const [value, setValue] = React.useState(0);
  const lastValue = useDebounce(value, 500);

  return (
    <div>
      <p>
        Current: {value} - Debounced: {lastValue}
      </p>
      <button onClick={() => setValue(value + 1)}>Increment</button>
    </div>
  );
};

ReactDOM.createRoot(document.getElementById('root')).render(
  <Counter />
);

翻译自：https://www.30secondsofcode.org/react/s/use-debounce