JS 获取某一年有多少周 每周开始/结束结束日期
<html> <head> <title></title> <meta charset="UTF-8" /> </head> <body> <script> function formatDig(num){ return num>9?''+num:'0'+num; } function formatDate(mill){ var y=new Date(mill); let raws= [ y.getFullYear(), formatDig(y.getMonth()+1), formatDig(y.getDate()), y.getDay()||7 ]; let format=['年','月','日 星期']; return String.raw({raw:raws},...format); } function* createWeeks(year){ const ONE_DAY=24*3600*1000; let start=new Date(year,0,1), end=new Date(year,11,31); let firstDay=start.getDay()|| 7, lastDay=end.getDay()||7; let startTime=+start, endTime=startTime+(7-firstDay)*ONE_DAY, _endTime=end-(7-lastDay)*ONE_DAY; yield [startTime,endTime]; startTime=endTime+ONE_DAY; endTime=endTime+7*ONE_DAY; while(endTime<_endTime){ yield [startTime,endTime]; startTime=endTime+ONE_DAY; endTime=endTime+7*ONE_DAY; } yield [startTime,+end]; } let index=1; for(let i of createWeeks(2020)){ let start=i[0], end=i[1]; console.log(`第${formatDig(index++)}周 ${formatDate(start)}-${formatDate(end)}`); } </script> </body> </html>