js 根据年月获取当月有多少天_js获取农历日期_及Js其它常用有用函数

　　  //根据年月获取当月有多少天
     function getDaysInMonth(year, month) {
         debugger;
         //parseInt(number,type)这个函数后面如果不跟第2个参数来表示进制的话，默认是10进制。 
         month = parseInt(month, 10); 
         var temp = new Date(year, month, 0);
         return temp.getDate();
     }

      //获取农历日期，是否闰月，生肖年，星期几
     function GetCurrentDateTime() {
         var d = new Date();
         var year = d.getFullYear();
         var month = d.getMonth() + 1;
         var date = d.getDate();
         var week = d.getDay();
         var hours = d.getHours();
         var minutes = d.getMinutes();
         var seconds = d.getSeconds();
         var ms = d.getMilliseconds();
         var curDateTime = year;
         if (month > 9)
             curDateTime = curDateTime + "年" + month;
         else
             curDateTime = curDateTime + "年0" + month;
         if (date > 9)
             curDateTime = curDateTime + "月" + date + "日";
         else
             curDateTime = curDateTime + "月0" + date + "日";
         if (hours > 9)
             curDateTime = curDateTime + " " + hours;
         else
             curDateTime = curDateTime + " 0" + hours;
         if (minutes > 9)
             curDateTime = curDateTime + ":" + minutes;
         else
             curDateTime = curDateTime + ":0" + minutes;
         if (seconds > 9)
             curDateTime = curDateTime + ":" + seconds;
         else
             curDateTime = curDateTime + ":0" + seconds;
         var weekday = "";
         if (week == 0)
             weekday = "星期日";
         else if (week == 1)
             weekday = "星期一";
         else if (week == 2)
             weekday = "星期二";
         else if (week == 3)
             weekday = "星期三";
         else if (week == 4)
             weekday = "星期四";
         else if (week == 5)
             weekday = "星期五";
         else if (week == 6)
             weekday = "星期六";
         curDateTime = curDateTime + " " + weekday;
         return curDateTime;
     } 

     var CalendarData = new Array(100);
     var madd = new Array(12);
     var tgString = "甲乙丙丁戊己庚辛壬癸";
     var dzString = "子丑寅卯辰巳午未申酉戌亥";
     var numString = "一二三四五六七八九十";
     var monString = "正二三四五六七八九十冬腊";
     var weekString = "日一二三四五六";
     var sx = "鼠牛虎兔龙蛇马羊猴鸡狗猪";
     var cYear, cMonth, cDay, TheDate;
     CalendarData = new Array(0xA4B, 0x5164B, 0x6A5, 0x6D4, 0x415B5, 0x2B6, 0x957, 0x2092F, 0x497, 0x60C96, 0xD4A, 0xEA5, 0x50DA9, 0x5AD, 0x2B6, 0x3126E, 0x92E, 0x7192D, 0xC95, 0xD4A, 0x61B4A, 0xB55, 0x56A, 0x4155B, 0x25D, 0x92D, 0x2192B, 0xA95, 0x71695, 0x6CA, 0xB55, 0x50AB5, 0x4DA, 0xA5B, 0x30A57, 0x52B, 0x8152A, 0xE95, 0x6AA, 0x615AA, 0xAB5, 0x4B6, 0x414AE, 0xA57, 0x526, 0x31D26, 0xD95, 0x70B55, 0x56A, 0x96D, 0x5095D, 0x4AD, 0xA4D, 0x41A4D, 0xD25, 0x81AA5, 0xB54, 0xB6A, 0x612DA, 0x95B, 0x49B, 0x41497, 0xA4B, 0xA164B, 0x6A5, 0x6D4, 0x615B4, 0xAB6, 0x957, 0x5092F, 0x497, 0x64B, 0x30D4A, 0xEA5, 0x80D65, 0x5AC, 0xAB6, 0x5126D, 0x92E, 0xC96, 0x41A95, 0xD4A, 0xDA5, 0x20B55, 0x56A, 0x7155B, 0x25D, 0x92D, 0x5192B, 0xA95, 0xB4A, 0x416AA, 0xAD5, 0x90AB5, 0x4BA, 0xA5B, 0x60A57, 0x52B, 0xA93, 0x40E95);
     madd[0] = 0;
     madd[1] = 31;
     madd[2] = 59;
     madd[3] = 90;
     madd[4] = 120;
     madd[5] = 151;
     madd[6] = 181;
     madd[7] = 212;
     madd[8] = 243;
     madd[9] = 273;
     madd[10] = 304;
     madd[11] = 334;

     function GetBit(m, n) {
         return (m >> n) & 1;
     }
     function e2c() {
         TheDate = (arguments.length != 3) ? new Date() : new Date(arguments[0], arguments[1], arguments[2]);
         var total, m, n, k;
         var isEnd = false;
         var tmp = TheDate.getYear();
         if (tmp < 1900) {
             tmp += 1900;
         }
         total = (tmp - 1921) * 365 + Math.floor((tmp - 1921) / 4) + madd[TheDate.getMonth()] + TheDate.getDate() - 38;

         if (TheDate.getYear() % 4 == 0 && TheDate.getMonth() > 1) {
             total++;
         }
         for (m = 0; ; m++) {
             k = (CalendarData[m] < 0xfff) ? 11 : 12;
             for (n = k; n >= 0; n--) {
                 if (total <= 29 + GetBit(CalendarData[m], n)) {
                     isEnd = true; break;
                 }
                 total = total - 29 - GetBit(CalendarData[m], n);
             }
             if (isEnd) break;
         }
         cYear = 1921 + m;
         cMonth = k - n + 1;
         cDay = total;
         if (k == 12) {
             if (cMonth == Math.floor(CalendarData[m] / 0x10000) + 1) {
                 cMonth = 1 - cMonth;
             }
             if (cMonth > Math.floor(CalendarData[m] / 0x10000) + 1) {
                 cMonth--;
             }
         }
     }

     function GetcDateString() {

         var y = cYear, m, d;

         var tmp = "";
         tmp += tgString.charAt((cYear - 4) % 10);
         tmp += dzString.charAt((cYear - 4) % 12);
         tmp += "(";
         tmp += sx.charAt((cYear - 4) % 12);
         tmp += ")年 ";
         if (cMonth < 1) {
             tmp += "(闰)";
             tmp += monString.charAt(-cMonth - 1);
             m = monString.charAt(-cMonth - 1);
         } else {
             tmp += monString.charAt(cMonth - 1);
             m = monString.charAt(cMonth - 1);
         }
         tmp += "月";
         tmp += (cDay < 11) ? "初" : ((cDay < 20) ? "十" : ((cDay < 30) ? "廿" : "三十"));
         d = (cDay < 11) ? "初" : ((cDay < 20) ? "十" : ((cDay < 30) ? "廿" : "三十"));
         if (cDay % 10 != 0 || cDay == 10) {
             tmp += numString.charAt((cDay - 1) % 10);
             d += numString.charAt((cDay - 1) % 10);
         }

         return cYear + "年" + m + "月" + d + "日";
         //return  tmp;
     }

     function GetLunarDay(solarYear, solarMonth, solarDay) {
         //solarYear = solarYear<1900?(1900+solarYear):solarYear;
         if (solarYear < 1921 || solarYear > 2020) {
             return "";
         } else {
             solarMonth = (parseInt(solarMonth) > 0) ? (solarMonth - 1) : 11;
             e2c(solarYear, solarMonth, solarDay);
             return GetcDateString();
         }
     }

     var D = new Date();
     var yy = D.getFullYear();
     var mm = D.getMonth() + 1;
     var dd = D.getDate();
     var ww = D.getDay();
     var ss = parseInt(D.getTime() / 1000);
     if (yy < 100) yy = "19" + yy;

     //调用
     alert(GetLunarDay(yy, mm, dd));