获取一段时间内从上次日期算起的天数？(非VBA)

// 上次日期和当前日期
var lastDate = new Date("2022-01-01");
var currentDate = new Date();

// 计算时间戳差值
var lastTimestamp = Math.floor(lastDate.getTime() / 1000);
var currentTimestamp = Math.floor(currentDate.getTime() / 1000);
var timestampDiff = currentTimestamp - lastTimestamp;

// 计算天数
var days = Math.floor(timestampDiff / 86400);

console.log("从上次日期算起的天数为：" + days);