时间格式化，显示一周前，一月前，刚刚

import dayjs from 'dayjs'
// 多久之前
export const getTime = (dateTimeStamp) => {
  const before = new Date(dateTimeStamp).getTime()
  const minute = 1000 * 60;
	const hour = minute * 60;
	const day = hour * 24;
	const month = day * 30;
	// const year = month * 12
	const now = new Date().getTime();
	const timeDiff = now - before;
  // dateTimeStamp存在
  if (before <= 0) return
	if(timeDiff < 0) return
	// const yearBefore = timeDiff / year
	const monthBefore = timeDiff / month // 几个月
	// const weekBefore =timeDiff / (7 * day)  // 几周
	const dayBefore =timeDiff / day  // 几天
	const hourBefore =timeDiff / hour // 小时
	// const minBefore =timeDiff / minute // 分钟
	if (monthBefore > 1) {// 大于一个月 显示年月日
		return  dayjs(dateTimeStamp).format('YYYY年MM月DD日')
	}	
	// else if(monthBefore>=1) {
	// 	return "" + parseInt(monthBefore) + "月前"
	// }
	// else if(weekBefore >= 1) {
	//   return  "" + parseInt(weekBefore) + "周前"
	// }
	else if(dayBefore>=1) {
		return ""+ parseInt(dayBefore) +"天前"
	}
	else if(hourBefore>=1) {
		return ""+ parseInt(hourBefore) +"小时前"
	}
	// else if(minBefore>=1) {
	// 	return ""+ parseInt(minBefore) +"分钟前"
	// } 
	else
	  return "刚刚"
}


// 格式化时间
export const getSpecificTime = (val) => {
	return dayjs(val).format('YYYY年MM月DD日 HH:mm')
}
// 使用
import { getTime } from '@/services/time'
computed: {
    timer() {
      return getTime(this.data.dateTime)
    },
  },
      <div> {{ timer }}</div>