Question

如何使用时刻js获得某个月的第二个星期二或获得某个月的第三个星期四。

我尝试找到一个解决方案，但没有成功。我自己写了并在下面发布了答案，如果你有更好的解决方案，你可以回答你的实施。

Answer 1

//get a preferred day of a month
var getGivenDateOfMonth = function (startDate, dayOfWeek, weekNumber) {
            var startOfMonth = moment(startDate).utc().startOf('month').startOf('isoweek');
            var dayOne = moment((moment(startDate, "YYYY-MM-DD").format("YYYY-MM") + "-01"),"YYYY-MM-DD");
            var studyDate;
            if (dayOne.isoWeekday() === 1) {
                studyDate = moment(startDate).utc().startOf('month').startOf('isoweek').add(dayOfWeek - 1, 'days')
                    .add(weekNumber, 'w');
            }
            else if (dayOne.isoWeekday() <= dayOfWeek) {
                studyDate = moment(startDate).utc().startOf('month').startOf('isoweek').add(dayOfWeek - 1, 'days')
                    .add(weekNumber - 1, 'w');
            } else {
                studyDate = moment(startDate).utc().startOf('month').startOf('isoweek').add(dayOfWeek - 1, 'days')
                    .add(weekNumber, 'w');
            }
            if (studyDate.month() == startOfMonth.month()) {
                studyDate = studyDate.subtract(1, 'w');
            }
            return studyDate;
        };

startDate 是指定月份的日期。
dayOfWeek 是js ISO星期和星期的时刻 weeknumber 是您想要的周数（1,2,3,4）

Answer 2

这是我在评论中链接的答案的更新版本。我使用weekday来使用一周中属于区域设置的日期，如果您总是希望星期日为0，星期六为6 ，则可以使用day。

var getGivenDateOfMonth = function (startDate, dayOfWeek, weekNumber) {
  // Start of the month of the given startDate
  var myMonth = moment(startDate).startOf('month');
  // dayOfWeek of the first week of the month
  var firstDayOfWeek = myMonth.clone().weekday(dayOfWeek);
  // Check if first firstDayOfWeek is in the given month
  if( firstDayOfWeek.month() != myMonth.month() ){
      weekNumber++;
  }
  // Return result
  return firstDayOfWeek.add(weekNumber-1, 'weeks');
}

// Examples
var secondMondayOfJuly = getGivenDateOfMonth('2017-07-10', 1, 2);
console.log(secondMondayOfJuly.format());
var thirdFridayOfJuly = getGivenDateOfMonth('2017-07-10', 5, 3);
console.log(thirdFridayOfJuly.format());

<script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.18.1/moment.min.js"></script>

Answer 3

＆＃13;

function nthDayOfMonth(month, year, day, weekNum){
   var nearestDay = moment(month + " " + year,"M YYYY").day(day);
   var nthDay = nearestDay.add(nearestDay.isSame(moment({month: month}),"month") ? weekNum - 1  : weekNum ,"weeks");
   return nthDay;
}

document.write(nthDayOfMonth(7,2017,3,3).format("L"));

＆＃13;

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.18.1/moment.min.js"></script>

＆＃13;

Answer 4

获取本月第二个星期二的日期：

var date = new Date();
var month_week = 2;	// 2nd Week
var week_day = 2;	// Tuesday

var first_week = moment(date).startOf("month").day(week_day);
var result = first_week.add(7 * (month_week - 1), "days");

console.log(result);

<script src="https://momentjs.com/downloads/moment.min.js"></script>

时刻js按星期和星期几获得特定日期

4 个答案: