React Hooks 计数器

const CounterWithInterval = () => {
    const [count, setCount] = useState(0);
    useEffect(() => {
        const timer = setInterval(() => {
            setCount((count) => count + 1);
        }, 1000);

        return () => {
            clearInterval(timer);
        };
    }, []);

    return <h1>Interval: {count}</h1>;
};