JS 获取（期号、当前日期、本周第一天、最后一天及当前月第一、最后天函数）

JS 获取（期号、当前日期、本周第一天、最后一天及当前月第一、最后天函数

/**
2 * 获取当前月期号
3 * 返回格式: YYYY-mm
4 * /
5 function getCurrentMonthIssue(date) {
6 let month = parseInt(date.getMonth() + 1);
7 if (month < 10) {
8 month = '0' + month
9 }
10 return date.getFullYear() + "-" + month;
11 }
12
13 /*
14 * 获取当前的日期
15 * 返回格式: YYYY-mm-dd
16 * /
17 function getCurrentDate(date) {
18 let month = parseInt(date.getMonth() + 1);
19 let day = date.getDate();
20 if (month < 10) {
21 month = '0' + month
22 }
23 if (day < 10) {
24 day = '0' + day
25 }
26 return date.getFullYear() + '-' + month + '-' + day;
27 }
28
29 /*
30 * 获取本周的第一天
31 * 返回格式: YYYY-mm-dd
32 * 例子: 当日为: 2020-11-27
33 * 返回日期为: 2020-11-23
34 * /
35 function getCurrentWeekFirstDay(date) {
36 let weekFirstDay = new Date(date - (date.getDay() - 1) * 86400000)
37 let firstMonth = Number(weekFirstDay.getMonth()) + 1
38
39 if (firstMonth < 10) {
40 firstMonth = '0' + firstMonth
41 }
42 let weekFirstDays = weekFirstDay.getDate();
43 if (weekFirstDays < 10) {
44 weekFirstDays = '0' + weekFirstDays;
45 }
46 return weekFirstDay.getFullYear() + '-' + firstMonth + '-' + weekFirstDays;
47 }
48
49 /*
50 * 获取本周的最后一天
51 * 返回格式: YYYY-mm-dd
52 * 例子: 当日为: 2020-11-27
53 * 返回日期为: 2020-11-29
54 * /
55 function getCurrentWeekLastDay(date) {
56 let weekFirstDay = new Date(date - (date.getDay() - 1) * 86400000)
57 let weekLastDay = new Date((weekFirstDay / 1000 + 6 * 86400) * 1000)
58 let lastMonth = Number(weekLastDay.getMonth()) + 1
59 if (lastMonth < 10) {
60 lastMonth = '0' + lastMonth
61 }
62 let weekLastDays = weekLastDay.getDate();
63 if (weekLastDays < 10) {
64 weekLastDays = '0' + weekLastDays;
65 }
66 return weekFirstDay.getFullYear() + '-' + lastMonth + '-' + weekLastDays;
67 }
68
69 /*
70 * 获取当前月的第一天
71 * 返回格式: YYYY-mm-dd
72 * 例子: 当日为: 2020-11-27
73 * 返回日期为: 2020-11-01
74 * /
75 function getCurrentMonthFirstDay() {
76 let date = new Date();
77 date.setDate(1);
78 let month = parseInt(date.getMonth() + 1);
79 let day = date.getDate();
80 if (month < 10) {
81 month = '0' + month
82 }
83 if (day < 10) {
84 day = '0' + day
85 }
86 return date.getFullYear() + '-' + month + '-' + day;
87 }
88
89 /*
90 * 获取当前月的最后一天
91 * 返回格式: YYYY-mm-dd
92 * 例子: 当日为: 2020-11-27
93 * 返回日期为: 2020-11-30
94 * */
95 function getCurrentMonthLastDay() {
96 let date = new Date();
97 let currentMonth = date.getMonth();
98 let nextMonth = ++currentMonth;
99 let nextMonthFirstDay = new Date(date.getFullYear(), nextMonth, 1);
100 let oneDay = 1000 * 60 * 60 * 24;
101 let lastTime = new Date(nextMonthFirstDay - oneDay);
102 let month = parseInt(lastTime.getMonth() + 1);
103 let day = lastTime.getDate();
104 if (month < 10) {
105 month = '0' + month
106 }
107 if (day < 10) {
108 day = '0' + day
109 }
110 return date.getFullYear() + '-' + month + '-' + day;
111 }
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使用方式：

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1 let date = new Date();
2 // 例当日时间是 2020-11-27
3 getCurrentMonthIssue(date); // result: 2020-11 --期号
4 getCurrentDate(date); // result: 2020-11-27 --当前日期
5 getCurrentWeekFirstDay(date); // result: 2020-11-23 --本周第一天时间
6 getCurrentWeekLastDay(date); // result: 2020-11-29 --本周最后一天时间
7 getCurrentMonthFirstDay(date); // result: 2020-11-01 --本月第一天时间
8 getCurrentMonthLastDay(date); // result: 2020-11-30 --本月最后一天时间