@zhouhua5982/date-utils/src/main.js

日期处理工具：主要功能为获取起止日期

const getCurrentDate = () => {
  return new Date()
}

/**
 * 获得本周起止时间
 */
const getCurrentWeek = () => {
  //起止日期数组
  let startStop = new Array()
  //获取当前时间
  let currentDate = getCurrentDate()
  //返回date是一周中的某一天
  let week = currentDate.getDay()
  //返回date是一个月中的某一天
  // let month = currentDate.getDate()

  //一天的毫秒数
  let millisecond = 1000 * 60 * 60 * 24
  //减去的天数
  let minusDay = week != 0 ? week - 1 : 6
  //本周 周一
  let monday = new Date(currentDate.getTime() - (minusDay * millisecond))
  //本周 周日
  let sunday = new Date(monday.getTime() + (6 * millisecond))
  //添加本周时间
  startStop.push(monday) //本周起始时间
  //添加本周最后一天时间
  startStop.push(sunday) //本周终止时间
  //返回
  return startStop
}

/**
 * 获取本月起止时间
 */
const getCurrentMonth = () => {
  //起止日期数组
  let startStop = new Array()
  //获取当前时间
  let currentDate = getCurrentDate()
  //获得当前月份0-11
  let currentMonth = currentDate.getMonth()
  //获得当前年份4位年
  let currentYear = currentDate.getFullYear()
  //求出本月第一天
  let firstDay = new Date(currentYear, currentMonth, 1)


  //当为12月的时候年份需要加1
  //月份需要更新为0 也就是下一年的第一个月
  if (currentMonth == 11) {
    currentYear++
    currentMonth = 0 //就为
  } else {
    //否则只是月份增加,以便求的下一月的第一天
    currentMonth++
  }


  //一天的毫秒数
  let millisecond = 1000 * 60 * 60 * 24
  //下月的第一天
  let nextMonthDayOne = new Date(currentYear, currentMonth, 1)
  //求出上月的最后一天
  let lastDay = new Date(nextMonthDayOne.getTime() - millisecond)

  //添加至数组中返回
  startStop.push(firstDay)
  startStop.push(lastDay)
  //返回
  return startStop
}

/**
 * 得到本季度开始的月份
 * @param {*} month 月份(月份从0-11)
 */
const getQuarterSeasonStartMonth = (month) => {
  // let quarterMonthStart = 0
  let spring = 0 // 春
  let summer = 3 // 夏
  let fall = 6 // 秋
  let winter = 9 // 冬
  // 月份从0-11
  if (month < 3) {
    return spring
  }

  if (month < 6) {
    return summer
  }

  if (month < 9) {
    return fall
  }

  return winter
}

/**
 * 获得指定月份的天数
 * @param {*} year 年份
 * @param {*} month 月份
 */
const getMonthDays = (year, month) => {
  //本月第一天 1-31
  let relativeDate = new Date(year, month, 1)
  //获得当前月份0-11
  let relativeMonth = relativeDate.getMonth()
  //获得当前年份4位年
  let relativeYear = relativeDate.getFullYear()

  //当为12月的时候年份需要加1
  //月份需要更新为0 也就是下一年的第一个月
  if (relativeMonth == 11) {
    relativeYear++
    relativeMonth = 0
  } else {
    //否则只是月份增加,以便求的下一月的第一天
    relativeMonth++
  }
  //一天的毫秒数
  let millisecond = 1000 * 60 * 60 * 24
  //下月的第一天
  let nextMonthDayOne = new Date(relativeYear, relativeMonth, 1)
  //返回得到上月的最后一天,也就是本月总天数
  return new Date(nextMonthDayOne.getTime() - millisecond).getDate()
}

/**
 * 获得本季度的起止日期
 */
const getCurrentSeason = () => {
  //起止日期数组
  let startStop = new Array()
  //获取当前时间
  let currentDate = getCurrentDate()
  //获得当前月份0-11
  let currentMonth = currentDate.getMonth()
  //获得当前年份4位年
  let currentYear = currentDate.getFullYear()
  //获得本季度开始月份
  let quarterSeasonStartMonth = getQuarterSeasonStartMonth(currentMonth)
  //获得本季度结束月份
  let quarterSeasonEndMonth = quarterSeasonStartMonth + 2

  //获得本季度开始的日期
  let quarterSeasonStartDate = new Date(currentYear, quarterSeasonStartMonth, 1)
  //获得本季度结束的日期
  let quarterSeasonEndDate = new Date(currentYear, quarterSeasonEndMonth, getMonthDays(currentYear, quarterSeasonEndMonth))
  //加入数组返回
  startStop.push(quarterSeasonStartDate)
  startStop.push(quarterSeasonEndDate)
  //返回
  return startStop
}

/**
 * 得到本年的起止日期
 */
const getCurrentYear = () => {
  //起止日期数组
  let startStop = new Array()
  //获取当前时间
  let currentDate = getCurrentDate()
  //获得当前年份4位年
  let currentYear = currentDate.getFullYear()

  //本年第一天
  let currentYearFirstDate = new Date(currentYear, 0, 1)
  //本年最后一天
  let currentYearLastDate = new Date(currentYear, 11, 31)
  //添加至数组
  startStop.push(currentYearFirstDate)
  startStop.push(currentYearLastDate)
  //返回
  return startStop
}

/**
 * 返回上一个月的第一天 Date 类型
 * @param {*} year 年份：0表示本年
 * @param {*} month 月份
 */
const getPriorMonthFirstDay = (year, month) => {
  //年份为0代表,是本年的第一月,所以不能减
  if (month == 0) {
    month = 11 //月份为上年的最后月份
    year-- //年份减1
    return new Date(year, month, 1)
  }
  //否则,只减去月份
  month--
  return new Date(year, month, 1)
}

/**
 * 获得上一月的起止日期
 */
const getPreviousMonth = () => {
  //起止日期数组
  let startStop = new Array()
  //获取当前时间
  let currentDate = getCurrentDate()
  //获得当前月份0-11
  let currentMonth = currentDate.getMonth()
  //获得当前年份4位年
  let currentYear = currentDate.getFullYear()
  //获得上一个月的第一天
  let priorMonthFirstDay = getPriorMonthFirstDay(currentYear, currentMonth)
  //获得上一月的最后一天
  let priorMonthLastDay = new Date(priorMonthFirstDay.getFullYear(), priorMonthFirstDay.getMonth(), getMonthDays(priorMonthFirstDay.getFullYear(), priorMonthFirstDay.getMonth()))
  //添加至数组
  startStop.push(priorMonthFirstDay)
  startStop.push(priorMonthLastDay)
  //返回
  return startStop
}

/**
 * 获得上一周的起止日期
 */
const getPreviousWeek = () => {
  //起止日期数组
  let startStop = new Array()
  //获取当前时间
  let currentDate = getCurrentDate()
  //返回date是一周中的某一天
  let week = currentDate.getDay()
  //返回date是一个月中的某一天
  let month = currentDate.getDate()
  //一天的毫秒数
  let millisecond = 1000 * 60 * 60 * 24
  //减去的天数
  let minusDay = week != 0 ? week - 1 : 6
  //获得当前周的第一天
  let currentWeekDayOne = new Date(currentDate.getTime() - (millisecond * minusDay))
  //上周最后一天即本周开始的前一天
  let priorWeekLastDay = new Date(currentWeekDayOne.getTime() - millisecond)
  //上周的第一天
  let priorWeekFirstDay = new Date(priorWeekLastDay.getTime() - (millisecond * 6))

  //添加至数组
  startStop.push(priorWeekFirstDay)
  startStop.push(priorWeekLastDay)

  return startStop
}

/**
 * 获取指定月份所在的季度
 * @param {*} month
 */
const getSeasonByMonth = (month) => {
  let season = 0
  if (month >= 0 && month < 3) {
    season = 9; // 冬
  } else if (month >= 3 && month < 6) {
    season = 0; // 春
  } else if (month >= 6 && month < 9) {
    season = 3; // 夏
  } else if (month >= 9 && month < 12) {
    season = 6; // 秋
  }
  return season
}

/**
 * 得到上季度的第一天的 Date 类型
 * @param {*} year 当前季度的年份
 * @param {*} month 当前季度的开始月份
 */
const getPriorSeasonFirstDay = (year, month) => {
  const season = getSeasonByMonth(month)
  let spring = 0 //春
  let summer = 3 //夏
  let fall = 6 //秋
  let winter = 9 //冬
  //月份从0-11
  switch (season) { //季度的真实月份
    case spring:
      //如果是第一季度则应该到去年的冬季
      year--
      month = winter
      break
    case summer:
      month = spring
      break
    case fall:
      month = summer
      break
    case winter:
      month = fall
      break
  }
  return new Date(year, month, 1)
}

/**
 * 得到上季度的起止日期
 */
const getPreviousSeason = () => {
  //起止日期数组
  let startStop = new Array()
  //获取当前时间
  let currentDate = getCurrentDate()
  //获得当前月份0-11
  let currentMonth = currentDate.getMonth() + 1
  //获得当前年份4位年
  let currentYear = currentDate.getFullYear()
  //上季度的第一天
  let priorSeasonFirstDay = getPriorSeasonFirstDay(currentYear, currentMonth)
  //上季度的最后一天
  let priorSeasonLastDay = new Date(priorSeasonFirstDay.getFullYear(), priorSeasonFirstDay.getMonth() + 2, getMonthDays(priorSeasonFirstDay.getFullYear(), priorSeasonFirstDay.getMonth() + 2))
  //添加至数组
  startStop.push(priorSeasonFirstDay)
  startStop.push(priorSeasonLastDay)
  return startStop
}

/**
 * 得到去年的起止日期
 */
const getPreviousYear = () => {
  //起止日期数组
  let startStop = new Array()
  //获取当前时间
  let currentDate = getCurrentDate()
  //获得当前年份4位年
  let currentYear = currentDate.getFullYear()
  currentYear--
  let priorYearFirstDay = new Date(currentYear, 0, 1)
  let priorYearLastDay = new Date(currentYear, 11, 1)
  //添加至数组
  startStop.push(priorYearFirstDay)
  startStop.push(priorYearLastDay)
  return startStop
}

export {
  getCurrentDate,
  getCurrentWeek,
  getCurrentMonth,
  getQuarterSeasonStartMonth,
  getMonthDays,
  getCurrentSeason,
  getCurrentYear,
  getPriorMonthFirstDay,
  getPreviousMonth,
  getPreviousWeek,
  getPriorSeasonFirstDay,
  getPreviousSeason,
  getPreviousYear
}