正序獲取近6個月年月

const getMonth = () => {
  let last6Months = []
  let today : any = new Date()
  let year = today.getFullYear()
  for (var i = 5; i >= 0; i--) {
    if ((today.getMonth() - 5 + i) < 0) {
      year = Number(year) - 1
    }
    last6Months[5 - i] = year + "年" + fillZero(Number(today.getMonth()) + 1, 5 - i) + "月" //這里+1是因為js 的月份是0-11
    }
    return last6Months
  }
//補零操作，保證月份為1位的時候補充前置0
const fillZero = (num : number, index : number) => {
  let month = ""
  if (num - index > 0 && num - index < 10) {
    month = "0" + (num - index)
  } else if (num - index <= 0) {
    month = 12 + num - index + ""
  } else if (num - index >= 10) {
    month = num - index + ""
  }
  return month
}