C#实现农历日历的方法

/// <summary>  
/// 获取对应日期的农历 
/// 
/// </summary>  
/// <param name="dtDay">公历日期</param> 
///
///<returns></returns>  
public string GetLunarCalendar(DateTime dtDay)
{
    string sYear = dtDay.Year.ToString(); string sMonth = dtDay.Month.ToString();
    string sDay = dtDay.Day.ToString();
    int year;
    int month;
    int day;
    try {
    year = int.Parse(sYear);
    month = int.Parse(sMonth);
    day = int.Parse(sDay);
    }
    catch {
    year = DateTime.Now.Year;
    month = DateTime.Now.Month;
    day = DateTime.Now.Day;
    }
    int nTheDate;
    int nIsEnd;
    int k, m, n, nBit, i;
    string calendar = string.Empty;
    //计算到初始时间1921年2月8日的天数：1921-2-8(正月初一)   
    nTheDate = (year - 1921) * 365 + (year - 1921) / 4 + day + MonthAdd[month - 1] - 38;
    if ((year % 4 == 0) && (month > 2)) nTheDate += 1;
    //计算天干，地支，月，日
    nIsEnd = 0; m = 0; k = 0; n = 0;
    while (nIsEnd != 1)
    {
 if (LunarData[m] < 4095) k = 11; else k = 12; n = k; while (n >= 0)
 {     //获取LunarData[m]的第n个二进制位的值 
     nBit = LunarData[m];
     for (i = 1; i < n + 1; i++) nBit = nBit / 2;
     nBit = nBit % 2;
     if (nTheDate <= (29 + nBit)) { nIsEnd = 1; break; }
     nTheDate = nTheDate - 29 - nBit; n = n - 1;
 }
 if (nIsEnd == 1) break; m = m + 1;
    }
    year = 1921 + m; month = k - n + 1; day = nTheDate;

 

    #region 格式化日期显示为三月廿四
    if (k == 12)
    {
 if (month == LunarData[m] / 65536 + 1)
     month = 1 - month;
 else if (month > LunarData[m] / 65536 + 1)
     month = month - 1;
    }
    //生肖//
    calendar = ShengXiao[(year - 4) % 60 % 12].ToString() + "年 ";