JS获取当前周从星期一到星期天的日期

需求：根据当天日期，获得所在周的所有日期，比如今天（2018-01-21）那么这一周的日期是：
[‘2018-01-15’,…’2018-01-21’]，要支持跨年，跨月。
注：星期一为一周的开始，星期天为结束
方法一：

const dateOfToday = Date.now() const dayOfToday = (new Date().getDay() + 7 - 1) % 7 const daysOfThisWeek = Array.from(new Array(7)) .map((_, i) => { const date = new Date(dateOfToday + (i - dayOfToday) 1000 60 60 24)

return date.getFullYear() +

 '-' +
 String(date.getMonth() + 1).padStart(2, '0') +
 '-' +
 String(date.getDate()).padStart(2, '0')

})

方法二(推荐)：

function getDates(currentTime) {//JS获取当前周从星期一到星期天的日期

var currentDate = new Date(currentTime)

var timesStamp = currentDate.getTime();

var currenDay = currentDate.getDay();

var dates = [];

for (var i = 0; i < 7; i++) {

   dates.push(new Date(timesStamp + 24 * 60 * 60 * 1000 * (i - (currenDay + 6) % 7)).toLocaleDateString().replace(/\//g, '-'));

}

return dates

}

方法三：

function getWeekDay(dateString) {

let dateStringReg = /^\d{4}[/-]\d{1,2}[/-]\d{1,2}$/;

if (dateString.match(dateStringReg)) {

   let presentDate = new Date(dateString),
       today = presentDate.getDay() !== 0 ? presentDate.getDay() : 7;
   return Array.from(new Array(7), function(val, index) {
       return formatDate(new Date(presentDate.getTime() - (today - index-1) * 24 * 60 * 60 * 1000));
   });

} else {

   throw new Error('dateString should be like "yyyy-mm-dd" or "yyyy/mm/dd"');

}

function formatDate(date) {

   return date.getFullYear() + '-' + (date.getMonth() + 1) + '-' + date.getDate();

}

}

console.log(getWeekDay(‘2018-1-8’));

文章来源：https://segmentfault.com/q/1010000012923451