js 获取当前的前n小时

const getHoursDistance = (date, hour) => {
  console.log("util getHoursDistance date: ", date)
  date.setHours(date.getHours() - hour);
  console.log("util getHoursDistance changeDate: ", date)
  const year = date.getFullYear()
  const month = date.getMonth() + 1
  const day = date.getDate()
  const hour = date.getHours()
  const minute = date.getMinutes()
  const second = date.getSeconds()

  return [year, month, day].map(formatNumber).join('/') + ' ' + [hour, minute, second].map(formatNumber).join(':')
}

const formatNumber = n => {
  n = n.toString()
  return n[1] ? n : '0' + n
}