javascript新日期获取时间无法与它们进行比较

Question

在我的后端，我用更新用户最后的活动

{ last_active: new Date().getTime() }

在前端，我这样做：

const statusexpire = props.last_active + 1000 * 60;
const currenttime = new Date().getTime();

useEffect(() => {
if (currenttime > statusexpire) {
socket.emit('deletelogged', props.id);
console.log('deleted' + props.id)
}
}, [currenttime, props.id]);

但看起来好像有什么地方做错了，我试了几个例子，但没有解决这个问题。

正在更新console.log的日志(currenttime，statuscpire(以查看输出：

1616162621335 "161616127040960000"
UserItem.js:40 1616162621338 "161616262117760000"
UserItem.js:40 1616162621345 "161616127040960000"
UserItem.js:40 1616162621346 "161616262117760000"
UserItem.js:40 1616162621398 "161616127040960000"
UserItem.js:40 1616162621400 "161616262117760000"
UserItem.js:40 1616162621410 "161616127040960000"
UserItem.js:40 1616162621416 "161616262117760000"
UserItem.js:40 1616162621425 "161616127040960000"
UserItem.js:40 1616162621427 "161616262117760000"
UserItem.js:40 1616162621435 "161616127040960000"
UserItem.js:40 1616162621440 "161616262117760000"
UserItem.js:40 1616162621447 "161616127040960000"
UserItem.js:40 1616162621449 "161616262117760000"
UserItem.js:40 1616162621456 "161616127040960000"
UserItem.js:40 1616162621460 "161616262117760000"
UserItem.js:40 1616162621466 "161616127040960000"
UserItem.js:40 1616162621468 "161616262117760000"
UserItem.js:40 1616162621482 "161616127040960000"
UserItem.js:40 1616162621491 "161616262117760000"
UserItem.js:40 1616162621497 "161616127040960000"
UserItem.js:40 1616162621502 "161616262117760000"
UserItem.js:40 1616162621513 "161616127040960000"
UserItem.js:40 1616162621519 "161616262117760000"
UserItem.js:40 1616162621527 "161616127040960000"
UserItem.js:40 1616162621528 "161616262117760000"
UserItem.js:40 1616162621535 "161616127040960000"
UserItem.js:40 1616162621541 "161616262117760000"
UserItem.js:40 1616162621549 "161616127040960000"

Answer 1

似乎props.last_active是字符串。试试怎么样

const statusexpire = parseInt(props.last_active) + 1000 * 60;

Answer 2

问题与props.last_active不是数字而是字符串的事实有关，因此props.last_active + 1000 * 60返回与1000 * 60连接的props.last_active。

要解决这个问题，只需要将props.last_active转换为整数，然后再将其与1000 * 60:相加

const statusexpire = parseInt(props.last_active) + 1000 * 60;