公历转农历

public static class ChineseCalendarHelper

{

public static string GetYear(DateTime time)

{

StringBuilder sb = new StringBuilder();

int year = calendar.GetYear(time);

int d;

do

{

d = year % 10;

sb.Insert(0, ChineseNumber[d]);

year = year / 10;

} while (year > 0);

return sb.ToString();

}

public static string GetMonth(DateTime time)

{

int month = calendar.GetMonth(time);

int year = calendar.GetYear(time);

int leap = 0;

//正月不可能闰月

for (int i = 3; i <= month; i++)

{

if (calendar.IsLeapMonth(year, i))

{

leap = i;

break; //一年中最多有一个闰月

}

}

if (leap > 0) month--;

return (leap == month + 1 ? "闰" : "") + ChineseMonthName[month - 1];

}

public static string GetDay(DateTime time)

{

return ChineseDayName[calendar.GetDayOfMonth(time) - 1];

}

public static string GetStemBranch(DateTime time)

{

int sexagenaryYear = calendar.GetSexagenaryYear(time);

string stemBranch = CelestialStem.Substring((sexagenaryYear - 1) % 10, 1) + TerrestrialBranch.Substring((sexagenaryYear - 1) % 12, 1);

return stemBranch;

}

private static ChineseLunisolarCalendar calendar = new ChineseLunisolarCalendar();

private static 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 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" };

}

///<summary>

///农历格式化类

///</summary>

public class ChineseCalendarFormatter : IFormatProvider, ICustomFormatter

{

//实现IFormatProvider

public object GetFormat(Type formatType)

{

if (formatType == typeof(ICustomFormatter))

return this;

else

return Thread.CurrentThread.CurrentCulture.GetFormat(formatType);

}

//实现ICustomFormatter

public string Format(string format, object arg, IFormatProvider formatProvider)

{

string s;

IFormattable formattable = arg as IFormattable;

if (formattable == null)

s = arg.ToString();

else

s = formattable.ToString(format, formatProvider);

if (arg.GetType() == typeof(DateTime))

{

DateTime time = (DateTime)arg;

switch (format)

{

case "D": //长日期格式

s = String.Format("{0}年{1}月{2}",

ChineseCalendarHelper.GetYear(time),

ChineseCalendarHelper.GetMonth(time),

ChineseCalendarHelper.GetDay(time));

break;

case "d": //短日期格式

s = String.Format("{0}年{1}月{2}", ChineseCalendarHelper.GetStemBranch(time),

ChineseCalendarHelper.GetMonth(time),

ChineseCalendarHelper.GetDay(time));

break;

case "M": //月日格式

s = String.Format("{0}月{1}", ChineseCalendarHelper.GetMonth(time),

ChineseCalendarHelper.GetDay(time));

break;

case "Y": //年月格式

s = String.Format("{0}年{1}月", ChineseCalendarHelper.GetYear(time),

ChineseCalendarHelper.GetMonth(time));

break;

default:

s = String.Format("{0}年{1}月{2}", ChineseCalendarHelper.GetYear(time),

ChineseCalendarHelper.GetMonth(time),

ChineseCalendarHelper.GetDay(time));

break;

}

}

return s;

}

}

客户端

string litCurrentDate= "(农历" + String.Format(new ChineseCalendarFormatter(), "{0:d}", DateTime.Today) + ")";