js获取当天0点的时间戳

function getDayTime () {
  let date = new Date()
  let times = date.getTime()
  let hour = date.getHours()
  let minute = date.getMinutes()
  let second = date.getSeconds()
  let dayTime = times - hour * 3600 * 1000 - minute * 60 * 1000 - second * 1000
  return dayTime
}