C# 實現陰陽歷算法

        if (day < 1 || day > calendar.GetDaysInMonth(year, month))
            throw new Exception("農歷日期輸入有誤");

        int num1 = 0, num2 = 0;
        int leapMonth = calendar.GetLeapMonth(year);

        if (((leapMonth == month + 1) && IsLeapMonth) || (leapMonth > 0 && leapMonth <= month))
            num2 = month;
        else
            num2 = month - 1;

        while (num2 > 0)
        {
            num1 += calendar.GetDaysInMonth(year, num2--);
        }

        DateTime dt = GetLunarNewYearDate(year);
        return dt.AddDays(num1 + day - 1);
    }

    /// <summary>
    /// 陰歷轉陽歷
    /// </summary>
    /// <param name="date">陰歷日期</param>
    /// <param name="IsLeapMonth">是否閏月</param>
    public static DateTime GetDateFromLunarDate(DateTime date, bool IsLeapMonth)
    {
        return GetDateFromLunarDate(date.Year, date.Month, date.Day, IsLeapMonth);
    }

    #endregion
    #region 從陰歷創建日歷

    /// <summary>
    /// 從陰歷創建日歷實體
    /// </summary>
    /// <param name="year">陰歷年</param>
    /// <param name="month">陰歷月</param>
    /// <param name="day">陰歷日</param>
    /// <param name="IsLeapMonth">是否閏月</param>
    public static ChineseCalendarInfo FromLunarDate(int year, int month, int day, bool IsLeapMonth)
    {
        DateTime dt = GetDateFromLunarDate(year, month, day, IsLeapMonth);
        return new ChineseCalendarInfo(dt);
    }
    /// <summary>
    /// 從陰歷創建日歷實體
    /// </summary>
    /// <param name="date">陰歷日期</param>
    /// <param name="IsLeapMonth">是否閏月</param>
    public static ChineseCalendarInfo FromLunarDate(DateTime date, bool IsLeapMonth)
    {
        return FromLunarDate(date.Year, date.Month, date.Day, IsLeapMonth);
    }

    /// <summary>
    /// 從陰歷創建日歷實體
    /// </summary>
    /// <param name="date">表示陰歷日期的8位數字，例如：20070209</param>
    /// <param name="IsLeapMonth">是否閏月</param>
    public static ChineseCalendarInfo FromLunarDate(string date, bool IsLeapMonth)
    {
        Regex rg = new System.Text.RegularExpressions.Regex(@"^\d{7}(\d)$");
        Match mc = rg.Match(date);
        if (!mc.Success)
        {
            throw new Exception("日期字符串輸入有誤！");
        }
        DateTime dt = DateTime.Parse(string.Format("{0}-{1}-{2}", date.Substring(0, 4), date.Substring(4, 2), date.Substring(6, 2)));
        return FromLunarDate(dt, IsLeapMonth);
    }

    #endregion

  private static ChineseLunisolarCalendar calendar = new ChineseLunisolarCalendar();
    public const string ChineseNumber = "〇一二三四五六七八九";
    public const string CelestialStem = "甲乙丙丁戊己庚辛壬癸";
    public const string TerrestrialBranch = "子丑寅卯辰巳午未申酉戌亥";
    public const string Animals = "鼠牛虎兔龍蛇馬羊猴雞狗豬";
    public static readonly string[] ChineseWeekName 
        = new string[] { "星期天", "星期一", "星期二", "星期三", "星期四", "星期五", "星期六" };
    public static readonly string[] ChineseDayName = new string[] {
"初一","初二","初三","初四","初五","初六","初七","初八","初九","初十",
"十一","十二","十三","十四","十五","十六","十七","十八","十九","二十",
"廿一","廿二","廿三","廿四","廿五","廿六","廿七","廿八","廿九","三十"};
    public static readonly string[] ChineseMonthName
        = new string[] { "正", "二", "三", "四", "五", "六", "七", "八", "九", "十", "十一", "十二" };
    public static readonly string[] Constellations 
        = new string[] { "白羊座", "金牛座", "雙子座", "巨蟹座", "獅子座", "處女座", "天秤座", "天蠍座", "射手座", "摩羯座", "水瓶座", "雙魚座" };
    public static readonly string[] BirthStones 
        = new string[] { "鑽石", "藍寶石", "瑪瑙", "珍珠", "紅寶石", "紅條紋瑪瑙", "藍寶石", "貓眼石", "黃寶石", "土耳其玉", "紫水晶", "月長石，血石" };

}