• JS 日记增加月份及处理2月28日和2月29日


    一般的方法中,2月28日和2月29日新增月份得到的日期都是28日或者29日,但是其他月份都是可以正常的加一个月的,所以可以回退一个月,遇到2月28日或2月29日时,可以退回1月31日,只要做好闰年的判断就好了。

     1 function addMonthPerfect(num) {
     2             var dateNow = new Date();
     3             if ((dateNow.getMonth()+1)==2) {
     4                 if (dateNow.getDate() == 29) {
     5                     dateNow = new Date(dateNow.getFullYear() + "-1-31");
     6                     num += 1;
     7                 } else if(dateNow.getDate()==28) {
     8                     if (!isLeapYear(dateNow.getFullYear())) {
     9                         dateNow = new Date(dateNow.getFullYear() + "-1-31");
    10                         num += 1;
    11                     }
    12                 }
    13             }
    14             return addMonth(dateNow, num).format("yyyy-MM-dd");
    15 }
    16 
    17 function isLeapYear(year) {
    18     var cond1 = year % 4 == 0;
    19     var cond2 = year % 100 != 0;
    20     var cond3 = year % 400 == 0;
    21     var cond = cond1 && cond2 || cond3;
    22     if (cond) {
    23         return true;
    24     } else {
    25         return false;
    26     }
    27 }
    28 
    29 function addMonth(date, num) {
    30     num = parseInt(num);
    31     var sDate = dateToDate(date);
    32 
    33     var sYear = sDate.getFullYear();
    34     var sMonth = sDate.getMonth() + 1;
    35     var sDay = sDate.getDate();
    36 
    37     var eYear = sYear;
    38     var eMonth = sMonth + num;
    39     var eDay = sDay;
    40     while (eMonth > 12) {
    41         eYear++;
    42         eMonth -= 12;
    43     }
    44 
    45     var eDate = new Date(eYear, eMonth - 1, eDay);
    46 
    47     while (eDate.getMonth() != eMonth - 1) {
    48         eDay--;
    49         eDate = new Date(eYear, eMonth - 1, eDay);
    50     }
    51 
    52     return eDate;
    53 };
    54 
    55 function dateToDate(date) {
    56     var sDate = new Date();
    57     if (typeof date == 'object'
    58       && typeof new Date().getMonth == "function"
    59       ) {
    60         sDate = date;
    61     }
    62     else if (typeof date == "string") {
    63         var arr = date.split('-');
    64         if (arr.length == 3) {
    65             sDate = new Date(arr[0] + '-' + arr[1] + '-' + arr[2]);
    66         }
    67     }
    68 
    69     return sDate;
    70 }
    71 Date.prototype.format = function (format) {
    72     if (format) { } else { format = "yyyy-MM-dd"; }
    73     var o = {
    74         "M+": this.getMonth() + 1, //month
    75         "d+": this.getDate(), //day
    76         "h+": this.getHours(), //hour
    77         "m+": this.getMinutes(), //minute
    78         "s+": this.getSeconds(), //second
    79         "q+": Math.floor((this.getMonth() + 3) / 3), //quarter
    80         "S": this.getMilliseconds() //millisecond
    81     }
    82     if (/(y+)/.test(format)) format = format.replace(RegExp.$1,
    83             (this.getFullYear() + "").substr(4 - RegExp.$1.length));
    84     for (var k in o) if (new RegExp("(" + k + ")").test(format))
    85         format = format.replace(RegExp.$1,
    86             RegExp.$1.length == 1 ? o[k] :
    87             ("00" + o[k]).substr(("" + o[k]).length));
    88     return format;
    89 }

      

  • 相关阅读:
    xgqfrms™, xgqfrms® : xgqfrms's offical website of GitHub!
    xgqfrms™, xgqfrms® : xgqfrms's offical website of GitHub!
    xgqfrms™, xgqfrms® : xgqfrms's offical website of GitHub!
    xgqfrms™, xgqfrms® : xgqfrms's offical website of GitHub!
    xgqfrms™, xgqfrms® : xgqfrms's offical website of GitHub!
    xgqfrms™, xgqfrms® : xgqfrms's offical website of GitHub!
    xgqfrms™, xgqfrms® : xgqfrms's offical website of GitHub!
    xgqfrms™, xgqfrms® : xgqfrms's offical website of GitHub!
    xgqfrms™, xgqfrms® : xgqfrms's offical website of GitHub!
    xgqfrms™, xgqfrms® : xgqfrms's offical website of GitHub!
  • 原文地址:https://www.cnblogs.com/MaxJoker/p/6529122.html
Copyright © 2020-2023  润新知