如何使用时刻迭代周数，周的开始/结束日期

Question

我怎样才能得到所有week number ， from/to date ？

下面的代码是我构建的用于显示特定月份的week number ， from/to date的代码，每当我在循环中插入 function 时它都会返回无限循环。

function getISOWeeksInMonth(month, year) {
    let weekStart = new Date(year, month - 1, 1);

    weekStart.setDate(weekStart.getDate() - (weekStart.getDay() || 7) + 1);

    let weekEnd = new Date(weekStart);
    weekEnd.setDate(weekEnd.getDate() + 6);

    let weekNum = moment(weekStart, "YYYY-MM-DD").week()

    let weeks = [];

    do {
        weeks.push({
            weekNum : weekNum++,
            start: new Date(weekStart),
            end: new Date(weekEnd)
        });

        weekStart.setDate(weekStart.getDate() + 7);
        weekEnd.setDate(weekEnd.getDate() + 7);
    } while (weekStart.getMonth() < month);

    return weeks;
}

_.forEach(moment.months(), function (month_name) {
    var month_number = moment().month(month_name).format("MM");

    getISOWeeksInMonth(month_number, 2022).forEach(week => console.log(
       'Week : ' + week.weekNum +
       '\nStart: ' + week.start.toDateString() + 
       '\nEnd  : ' + week.end.toDateString())
    );
})

结果应返回week number列表， from/to date
样本 Url： https://savvytime.com/week-number/philippines/2022

这是我运行 function 外循环时的示例：

 function getISOWeeksInMonth(month, year) { let weekStart = new Date(year, month - 1, 1); weekStart.setDate(weekStart.getDate() - (weekStart.getDay() || 7) + 1); let weekEnd = new Date(weekStart); weekEnd.setDate(weekEnd.getDate() + 6); let weekNum = moment(weekStart, "YYYY-MM-DD").week() let weeks = []; do { weeks.push({ weekNum: weekNum++, start: new Date(weekStart), end: new Date(weekEnd) }); weekStart.setDate(weekStart.getDate() + 7); weekEnd.setDate(weekEnd.getDate() + 7); } while (weekStart.getMonth() < month); return weeks; } getISOWeeksInMonth(1, 2022).forEach(week => console.log( 'Week: ' + week.weekNum + '\nStart: ' + week.start.toDateString() + '\nEnd: ' + week.end.toDateString()) );

 <script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.29.2/moment.min.js"></script>

Answer 1

 function getISOWeeksInMonth(month, year) { let weekStart = new Date(year, month - 1, 1); weekStart.setDate(weekStart.getDate() - (weekStart.getDay() || 7) + 1); let weekEnd = new Date(weekStart); weekEnd.setDate(weekEnd.getDate() + 6); let weeks = []; do { let weekNum = moment(weekStart, "YYYY-MM-DD").week() weeks.push({ weekNum: weekNum, start: new Date(weekStart), end: new Date(weekEnd) }); weekStart.setDate(weekStart.getDate() + 7); weekEnd.setDate(weekEnd.getDate() + 7); } while (weekStart.getMonth() < month && (weekStart.getMonth() || (month < 12) )); return weeks; } let _ = moment.months() _.forEach(function (month_name) { var month_number = moment().month(month_name).format("MM"); getISOWeeksInMonth(month_number, 2022).forEach(week => console.log( 'Week: ' + week.weekNum + '\nStart: ' + week.start.toDateString() + '\nEnd: ' + week.end.toDateString()) ); })

 <script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.29.2/moment.min.js"></script>

当您计算 12 月（第 12 个月）的周数时，您从前一个月（11 月，即 11 日）的最后一周开始，并且在您的do {...} while循环中，您将 7 天添加到weekStart 。 到目前为止一切顺利，但是您的while (weekStart.getMonth() < month)正在检查weekStart.getMonth()的 0-11 值，当它从 11 向前滚动时，它不会转到 12，而是转到 0。所以它总是小于 12（12 月！）！

您可以通过将while调整为以下方式来解决此问题：

while (weekStart.getMonth() < month && (weekStart.getMonth() || (month < 12) ))