javascript日期操作函数-CavinHuangのBlog-http://blog.zukmb.cn

函数目录
getFormatDateStr 获得指定日期格式的字符串；
getDayPrevAfter 获得n天前/后的日期；

formatDateWithTimeZone 格式化日期带时区，ISO 8601；
countDownBySecond 倒计时；
monthSize 获得指定日期所在月的天数；
getCalendarMonth 获得指定日期所在月的第一周到第四/五周的数据组合；
getOneDateWeekIndex 获得指定的某天所在该月的第几周，下标从0开始；
下面是详细的说明：

getFormatDateStr

/**
 * [zeroPadding 小于10的数字补0，必填]
 * @param  &#123;[Int]&#125; value [description]
 * @return &#123;[String]&#125;       [description]
 */
export function zeroPadding(value)&#123;
  return value < 10 ? `0$&#123;value&#125;` : value;
&#125;

/**
 * [_isDateStrSeparatorCh 判断日期格式字符串的分隔符是否是中文]
 * @param  &#123;[String]&#125; str [必填]
 * @return &#123;[String]&#125;     [分隔符]
 */
function _getDateStrSeparator(str, startIndex, endIndex) &#123;
  startIndex = startIndex ? startIndex : 4;
  endIndex = endIndex ? endIndex : 5;
  let separator = str.slice(startIndex, endIndex);
  if (separator === '年' || separator === '月' ) &#123;
    separator = 'Ch';
  &#125;
  return separator;
&#125;

/**
 * [_isDateStrSeparatorCh 判断日期格式字符串的分隔符是否是中文]
 * @param  &#123;[String]&#125; str [必填]
 * @return &#123;[String]&#125;     [分隔符]
 */
function _isDateStrSeparatorCh(str) &#123;
  if ( str.indexOf('年')!=-1 || str.indexOf('月')!=-1 ) &#123;
    return true;
  &#125;
  return false;
&#125;

/**
 * [getFormatDateStr 获得指定日期格式的字符串]
 * @param  &#123;[String or Date]&#125;  date  [要转换的日期，必填]
 * @param  &#123;[String]&#125;  dateFormatStr     [要转化的目标格式，必填，2016-11-22之间的分隔符可任意，可选项：
 * 'yyyy-mm-dd hh:mm:ss','yyyy/mm/dd hh:mm:ss','yyyy.mm.dd hh:mm:ss','yyyy年mm月dd hh:mm:ss',
 * 'yyyy-mm-dd hh:mm',
 * 'mm-dd hh:mm',
 * 'yyyy-mm-dd',
 * 'mm-dd',
 * 'hh:mm:ss',
 * 'hh:mm'
 * ]
 * @return &#123;[String]&#125;                [时间格式字符串]
 */
export function getFormatDateStr(date, dateFormatStr) &#123;

    if ( !(date instanceof Date) ) &#123;
      if ( date.indexOf('-') != -1 ) &#123;
        date.replace(/\-/g,'/');
      &#125;
          date = new Date(date);
      &#125;

    dateFormatStr = dateFormatStr.toLowerCase();
    if (!dateFormatStr)&#123;
      return false;
    &#125;

    let returnStr = '',
        separator = _getDateStrSeparator(dateFormatStr),
        year = date.getFullYear(),
            month = date.getMonth() + 1,
            day = date.getDate(),
            hour = date.getHours(),
            minute = date.getMinutes(),
        second = date.getSeconds();

    if ( /^yyyy(.&#123;1&#125;)mm(.&#123;1&#125;)dd hh:mm:ss$/.test(dateFormatStr) ) &#123;
      if (_isDateStrSeparatorCh(dateFormatStr)) &#123;
        returnStr = `$&#123;year&#125;年$&#123;zeroPadding(month)&#125;月$&#123;zeroPadding(day)&#125;日`;
      &#125; else &#123;
        separator =
        returnStr = `$&#123;year&#125;$&#123;separator&#125;$&#123;zeroPadding(month)&#125;$&#123;separator&#125;$&#123;zeroPadding(day)&#125;`;
      &#125;
      returnStr += ` $&#123;zeroPadding(hour)&#125;:$&#123;zeroPadding(minute)&#125;:$&#123;zeroPadding(second)&#125;`;
    &#125; else if ( /^yyyy(.&#123;1&#125;)mm(.&#123;1&#125;)dd hh:mm$/.test(dateFormatStr) ) &#123;
      if (_isDateStrSeparatorCh(dateFormatStr)) &#123;
        returnStr = `$&#123;year&#125;年$&#123;zeroPadding(month)&#125;月$&#123;zeroPadding(day)&#125;日`;
      &#125; else &#123;
        returnStr = `$&#123;year&#125;$&#123;separator&#125;$&#123;zeroPadding(month)&#125;$&#123;separator&#125;$&#123;zeroPadding(day)&#125;`;
      &#125;
      returnStr += ` $&#123;zeroPadding(hour)&#125;:$&#123;zeroPadding(minute)&#125;`;
    &#125; else if ( /^mm(.&#123;1&#125;)dd hh:mm$/.test(dateFormatStr) ) &#123;
      if (_isDateStrSeparatorCh(dateFormatStr)) &#123;
        returnStr = `$&#123;zeroPadding(month)&#125;月$&#123;zeroPadding(day)&#125;日`;
      &#125; else &#123;
        separator = _getDateStrSeparator(dateFormatStr, 2, 3);
        returnStr = `$&#123;zeroPadding(month)&#125;$&#123;separator&#125;$&#123;zeroPadding(day)&#125;`;
      &#125;
      returnStr += ` $&#123;zeroPadding(hour)&#125;:$&#123;zeroPadding(minute)&#125;`;
    &#125; else if ( /^yyyy(.&#123;1&#125;)mm(.&#123;1&#125;)dd$/.test(dateFormatStr) ) &#123;
      if (_isDateStrSeparatorCh(dateFormatStr)) &#123;
        returnStr = `$&#123;year&#125;年$&#123;zeroPadding(month)&#125;月$&#123;zeroPadding(day)&#125;日`;
      &#125; else &#123;
        returnStr = `$&#123;year&#125;$&#123;separator&#125;$&#123;zeroPadding(month)&#125;$&#123;separator&#125;$&#123;zeroPadding(day)&#125;`;
      &#125;
    &#125; else if ( /^mm(.&#123;1&#125;)dd$/.test(dateFormatStr) ) &#123;
      if (_isDateStrSeparatorCh(dateFormatStr)) &#123;
        returnStr = `$&#123;zeroPadding(month)&#125;月$&#123;zeroPadding(day)&#125;日`;
      &#125; else &#123;
        separator = _getDateStrSeparator(dateFormatStr, 2, 3);
        returnStr = `$&#123;zeroPadding(month)&#125;$&#123;separator&#125;$&#123;zeroPadding(day)&#125;`;
      &#125;
    &#125; else if ( /^hh:mm:ss$/.test(dateFormatStr) ) &#123;
      returnStr = `$&#123;zeroPadding(hour)&#125;:$&#123;zeroPadding(minute)&#125;:$&#123;zeroPadding(second)&#125;`;
    &#125; else if ( /^hh:mm$/.test(dateFormatStr) ) &#123;
      returnStr = `$&#123;zeroPadding(hour)&#125;:$&#123;zeroPadding(minute)&#125;`;
    &#125;

  return returnStr;

&#125;

getDayPrevAfter

/**
 * [getDayPrevAfter 获得n天前/后的日期]
 * @param  &#123;[String]&#125; date    [日期，非必填参数，表示调用时的时间]
 * @param  &#123;[String]&#125; type    [前一天还是后一天，非必填参数，默认后一天]
 * @param  &#123;[Int]&#125; daysNum [天数，非必填参数，默认一天]
 * @return &#123;[Date]&#125;         [description]
 */
export function getDayPrevAfter(date, type, daysNum) &#123;

  date = date ? date : new Date();
  type = type ? type : 'after';
  daysNum = daysNum ? daysNum : 1;

  if ( !(date instanceof Date) ) &#123;
    if ( date.indexOf('-') != -1 ) &#123;
      date.replace(/\-/g,'/');
    &#125;
    date = new Date(date);
  &#125;

  let returnDate = date;
  if (type === 'prev') &#123;
    returnDate = new Date(date.getTime() - (daysNum * 24 * 60 * 60 * 1000));
  &#125; else if (type === 'after') &#123;
    returnDate = new Date(date.getTime() + (daysNum * 24 * 60 * 60 * 1000));
  &#125;
  return returnDate;

&#125;

formatDateWithTimeZone

/**
 * [formatDateWithTimeZone 格式化日期带时区，ISO 8601]
 * @param  &#123;[Date]&#125; date [日期，非必填参数，表示调用时的时间]
 * @return &#123;[String]&#125;     [ISO 8601格式的日期，example: 2016-11-21T14:09:15+08:00]
 */
export function formatDateWithTimeZone(date) &#123;

  date = date ? date : new Date();
  if ( !(date instanceof Date) ) &#123;
    if ( date.indexOf('-') != -1 ) &#123;
      date.replace(/\-/g,'/');
    &#125;
    date = new Date(date);
  &#125;

  let tzo = -date.getTimezoneOffset(),
      dif = tzo >= 0 ? '+' : '-',
      pad = function (num) &#123;
          let norm = Math.abs(Math.floor(num));
          return zeroPadding(norm);
      &#125;;
    return `$&#123;date.getFullYear()&#125;-$&#123;pad(date.getMonth() + 1)&#125;-$&#123;pad(date.getDate())&#125;T$&#123;pad(date.getHours())&#125;:$&#123;pad(date.getMinutes())&#125;:$&#123;pad(date.getSeconds())&#125;$&#123;dif&#125;$&#123;pad(tzo / 60)&#125;:$&#123;pad(tzo % 60)&#125;`;

&#125;

countDownBySecond

/**
 * [countDownBySecond 倒计时]
 * @param  &#123;[Int]&#125; restSeconds   [剩余秒数，必填]
 * @param  &#123;[Int]&#125; timeInterval   [时间间隔，非必填，默认1000ms]
 * @param  &#123;[Function]&#125; func   [每倒计时一次，就需要执行一次的回调函数名，非必填]
 * @param  &#123;[Function]&#125; endFun [倒计时结束需要执行的函数名，非必填]
 * @return &#123;[null]&#125;        [无返回值]
 */
export function countDownBySecond(restSeconds, timeInterval, func, endCallback) &#123;
    let timer = null;
    let total = restSeconds;
    timeInterval = timeInterval ? timeInterval : 1000;
    timer = setInterval(function() &#123;
        --total;
        if (total <= 0) &#123;
            clearInterval(timer);
            endCallback && endCallback();
        &#125;
        func && func(total);
    &#125;, timeInterval);
&#125;

monthSize

/**
 * [monthSize 获得指定日期所在月的天数]
 * @param  &#123;[Date]&#125; oDate [指定的日期，非必填，默认为当天]
 * @return &#123;[Int]&#125;       [总天数]
 */
function monthSize(oDate) &#123;
    oDate = oDate ? oDate : new Date();
    let year = oDate.getFullYear(),
        month = oDate.getMonth(),
        _oDate = new Date();
    _oDate.setFullYear(year);
    _oDate.setMonth(month + 1, 0);
    return _oDate.getDate();
&#125;

getCalendarMonth

/**
 * [getCalendarMonth 获得指定日期所在月的第一周到第四/五周的数据组合，形如：
 * [&#123;
    "date": "2016/10/30", //日期字符串
    "dateNum": 30,  //日
    "isCurMonth": false, //是否当前月
    "weekIndex": 0 //是本月的第几周，下标从0开始
  &#125;,&#123;
    "date": "2016/10/31",
    "dateNum": 31,
    "isCurMonth": false,
    "weekIndex": 0
  &#125;,&#123;
    "date": "2016/11/1",
    "dateNum": 1,
    "day": 2,
    "isCurMonth": true,
    "isToday": false,
    "weekIndex": 0
  &#125;]
  ]
 * @param  &#123;[Date]&#125; param [指定的日期，非必填，默认为当天]
 * @return &#123;[Array]&#125;       [获得指定日期所在月的第一周到第四/五周的数据组合]
 */
export function getCalendarMonth(date) &#123;
    date = date ? date : new Date();
    let y = date.getFullYear();
    let m = date.getMonth();
    let _m;
    let firstDay = new Date(y, m, 1).getDay(); //当月第一天 周期
    let days = monthSize(date);//当月天数
    let prevMonthDays = monthSize(new Date(y, m - 1));//上月天数
    let initPrevDay = prevMonthDays - firstDay;
    let lines = Math.ceil((firstDay + days) / 7);
    _m = new Array(lines * 7);
    let nextMonthDay = 0;

    for (let i = 0; i < _m.length; i++) &#123;
        let weekIndex = parseInt(i / 7);
        if (i < firstDay) &#123;
            let date = ++initPrevDay;
            if (m === 0 && date > 7) &#123;
                _m[i] = &#123;
                    isCurMonth: false,
                    dateNum: date,
                    weekIndex,
                    date: `$&#123;y - 1&#125;/$&#123;12&#125;/$&#123;date&#125;`
                &#125;;
            &#125; else &#123;
                _m[i] = &#123;
                    isCurMonth: false,
                    dateNum: date,
                    weekIndex,
                    date: `$&#123;y&#125;/$&#123;m&#125;/$&#123;date&#125;`
                &#125;;
            &#125;
        &#125; else if (i >= (firstDay + days)) &#123;
            let date = ++nextMonthDay;

            if (m === 11 && date <= 7) &#123;
                _m[i] = &#123;
                    isCurMonth: false,
                    dateNum: date,
                    weekIndex,
                    date: `$&#123;y + 1&#125;/$&#123;1&#125;/$&#123;date&#125;`
                &#125;;
            &#125; else &#123;
                _m[i] = &#123;
                    isCurMonth: false,
                    dateNum: date,
                    weekIndex,
                    date: `$&#123;y&#125;/$&#123;m + 2&#125;/$&#123;date&#125;`
                &#125;;
            &#125;
        &#125; else &#123;
            let _date = i - firstDay + 1;
            let today = new Date();
            let today_y = today.getFullYear();
            let today_m = today.getMonth();
            let today_d = today.getDate();
            let isToday = today_y === y && today_m === m && today_d === _date ? true : false;
            _m[i] = &#123;
                dateNum: _date, //日期
                day: i % 7, //周期
                weekIndex,
                isCurMonth: true,
                isToday,
                date: `$&#123;y&#125;/$&#123;m + 1&#125;/$&#123;_date&#125;`
            &#125;;
        &#125;
    &#125;
    return _m;
&#125;

getOneDateWeekIndex

/**
 * [getOneDateWeekIndex 获得指定的某天所在该月的第几周，下标从0开始]
 * @param  &#123;[Date]&#125; date [指定的日期，非必填，默认为当天]
 * @return &#123;[Int]&#125;      [在该月的第几周]
 */
export function getOneDateWeekIndex(date) &#123;
    date = date ? date : new Date();
    let monthDays = getCalendarMonth(date);
    let dateString = getFormatDateStr(date, '/', true, false, false);
    let returnDate = monthDays.filter(item => &#123;
        return item.date === dateString;
    &#125;);
    let weekIndex = returnDate[0].weekIndex;
    return weekIndex ? weekIndex : 0;
&#125;