取当前时间的前几天日期，返回数组

getDateTime (num) {
  const currentTime = new Date() // 当前时间
  let time = Array.from({ length: num }, (item, index) => new Date(currentTime.getTime() - (num - index) * 8.64e7))
  let date = []
  time.forEach(item => {
    date.push([[item.getFullYear(), item.getMonth() + 1, item.getDate()].join('-')].join(' ').replace(/(?=\b\d\b)/g, '0'))
  })
  return date
}
console.log(getDateTime(7)) // ["2022-10-04","2022-10-05","2022-10-06","2022-10-07","2022-10-08","2022-10-09","2022-10-10"]

获取当前时间的前几天日期并包含当天时，(num-index) 调整为 (num-index-1)