javascript - 农历日期的倒计时效果怎么做？？

Question

做一个生日的倒计时，因为一般生日都是按农历来算的。。
有没有大神会做的。。
只找到一个获取当天农历日期的JS代码。。

`

<script>
        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 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);
            } else {
                tmp += monString.charAt(cMonth - 1);
            }
            tmp += "月";
            tmp += (cDay < 11) ? "初" : ((cDay < 20) ? "十" : ((cDay < 30) ? "廿" : "三十"));
            if (cDay % 10 != 0 || cDay == 10) {
                tmp += numString.charAt((cDay - 1) % 10);
            }
            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;
        
        function showCal() {
            document.write(GetLunarDay(yy, mm, dd));
        }
    </script>
    <script type="text/javascript">
        showCal();
    </script>`

Answer 1

找段把农历推算成公历的代码，再把农历生日按公历日期来计算倒计时不就简单了

Answer 2

就像 @边城 说的，先转成公历再算差。我写过一段代码，里面有农历转公历的函数，不过是 Python 的。反正思路就是给定一个农历日期（包含公元年份），穷举当年每一天的农历日期，如果和给定的一样，那么就是这一天，返回公历日期。