示例代码
import React, { useState, useEffect } from 'react';
function Count() {
const [countSec, setCountSec] = useState(0);
useEffect(() => {
if (countSec) {
const id = setTimeout(() => {
setCountSec(countSec - 1);
}, 1000);
return () => clearTimeout(id);
}
}, [countSec]);
return (
<button onClick={() => setCountSec(60)}>
{
!countSec ? 'start count' : countSec
}
</button>
);
}
export default Count;