js获取选中日期的当周的周一和周日

 1 console.log(getNowDateAndNowWeek(1539187200000));
 2     
 3     /**
 4      * 获取当月的第几周
 5      * a = d = 当前日期
 6      * b = 6 - w = 当前周的还有几天过完(不算今天)
 7      * a + b 的和在除以7 就是当天是当前月份的第几周
 8     */
 9     function getMonthWeek(a, b, c) {
10 
11         var date = new Date(a, parseInt(b) - 1, c), w = date.getDay(), d = date.getDate();
12         return Math.ceil(
13             (d + 6 - w) / 7
14         );
15     };
16 
17     
18     /**
19      * 获取选择当前的第几周，当前的周一、周日
20      * time 选择日期的时间戳
21      */
22     function getNowDateAndNowWeek(time) {
23         //选中的时间戳
24         var timestamp = time;
25         var serverDate = new Date(time);
26 
27         //本周周日的的时间
28         var sundayTiem = timestamp + ((7 - serverDate.getDay()) * 24 * 60 * 60 * 1000)
29         var SundayData = new Date(sundayTiem);
30         //年
31         var tomorrowY = SundayData.getFullYear();
32         //月
33         var tomorrowM = (SundayData.getMonth() + 1 < 10 ? '0' + (SundayData.getMonth() + 1) : SundayData.getMonth() + 1);
34         //日
35         var tomorrowD = SundayData.getDate() < 10 ? '0' + SundayData.getDate() : SundayData.getDate();
36         console.log('周日：  ' + tomorrowY + '-' + tomorrowM + '-' + tomorrowD);
37 
38         // 本周周一的时间
39         var mondayTime = timestamp - ((serverDate.getDay() - 1) * 24 * 60 * 60 * 1000)
40         var mondayData = new Date(mondayTime);
41         //年
42         var mondayY = mondayData.getFullYear();
43         //月
44         var mondayM = (mondayData.getMonth() + 1 < 10 ? '0' + (mondayData.getMonth() + 1) : mondayData.getMonth() + 1);
45         //日
46         var mondayD = mondayData.getDate() < 10 ? '0' + mondayData.getDate() : mondayData.getDate();
47         var nowWeek = getMonthWeek(tomorrowY, tomorrowM, tomorrowD);
48         //输出值
49         var config = {
50             SunDay: tomorrowY + '/' + tomorrowM + '/' + tomorrowD,
51             Monday: mondayY + '/' + mondayM + '/' + mondayD,
52             nowWeek: nowWeek
53         }
54         return config;
55     }