我有一个应用程序，可以在人们生病时进行登记，并在此事件发生后的一定工作日内向经理发送通知。
我可以使用 DateTime 的属性来跳过周末，但如何跳过假期？
我在某处读到，教堂假期是从复活节开始计算的。但如何呢？我首先如何找到复活节？
跳过日期之间的假期和计算复活节是两种不同的野兽，你可能想要前者。
您的申请应该维护一个假期列表，正如 @GeneMyers 关于
Holidays in United States通过此列表，您可以使用如下代码：
private static void Main(string[] args)
{
var start = new DateTime(2015, 01, 01); // Thusday
var finish = new DateTime(2015, 01, 31); // Saturday
var totalDays = finish.Subtract(start).TotalDays; // 30 days
var test1 = GetWorkingDays(start, finish, false, new List<DateTime>()); // should be 30
var test2 = GetWorkingDays(start, finish, true , new List<DateTime>()); // should be 21
var test3 = GetWorkingDays(start, finish, true , new List<DateTime> // should be 19
{
new DateTime(2015, 01, 01), // New Year's Day
new DateTime(2015, 01, 09), // Random holiday
new DateTime(2015, 01, 25), // Sao Paulo city foundation, sunday
});
}
public static int GetWorkingDays(DateTime from, DateTime to,
bool skipWeekends, IEnumerable<DateTime> holidays)
{
var totalDays = (int)to.Subtract(from).TotalDays;
var isHoliday = new Func<DateTime, bool>(date =>
holidays.Contains(date));
var isWeekend = new Func<DateTime, bool>(date =>
date.DayOfWeek == DayOfWeek.Saturday ||
date.DayOfWeek == DayOfWeek.Sunday);
return Enumerable
.Range (0, totalDays + 1)
.Select(days => from.AddDays(days))
.Count (date => (!skipWeekends || !isWeekend(date)) && !isHoliday(date)) - 1;
}
我会使用您所在区域的已知假期表，而不是尝试计算它们 - 例如，Outlook 允许您导入假期列表。还要记住，东正教复活节和“西方”复活节是有区别的。
如果您特别希望计算公历复活节，请查看此 BASIC 代码，如果您仍然愿意自己执行此操作，则可以轻松将其移植到 C#。
我创建了以下类来添加/减去/计算工作日：它包括一个计算复活节的方法（也可用于检索相关的复活节星期一和/或耶稣受难日）和一个可自定义的 DateTimes IEnumerable 来视为“节假日”（例如，城镇圣守护神节或公司假期）。
以下是相关源代码：值得注意的是，主要方法（AddBusinessDays、SubtractBusinessDays 和 GetBusinessDays）既可以用作静态辅助方法，也可以用作扩展方法。
/// <summary>
/// Helper/extension class for manipulating date and time values.
/// </summary>
public static class DateTimeExtensions
{
/// <summary>
/// Calculates the absolute year difference between two dates.
/// </summary>
/// <param name="dt1"></param>
/// <param name="dt2"></param>
/// <returns>A whole number representing the number of full years between the specified dates.</returns>
public static int Years(DateTime dt1,DateTime dt2)
{
return Months(dt1,dt2)/12;
//if (dt2<dt1)
//{
// DateTime dt0=dt1;
// dt1=dt2;
// dt2=dt0;
//}
//int diff=dt2.Year-dt1.Year;
//int m1=dt1.Month;
//int m2=dt2.Month;
//if (m2>m1) return diff;
//if (m2==m1 && dt2.Day>=dt1.Day) return diff;
//return (diff-1);
}
/// <summary>
/// Calculates the absolute year difference between two dates.
/// Alternative, stand-alone version (without other DateTimeUtil dependency nesting required)
/// </summary>
/// <param name="start"></param>
/// <param name="end"></param>
/// <returns></returns>
public static int Years2(DateTime start, DateTime end)
{
return (end.Year - start.Year - 1) +
(((end.Month > start.Month) ||
((end.Month == start.Month) && (end.Day >= start.Day))) ? 1 : 0);
}
/// <summary>
/// Calculates the absolute month difference between two dates.
/// </summary>
/// <param name="dt1"></param>
/// <param name="dt2"></param>
/// <returns>A whole number representing the number of full months between the specified dates.</returns>
public static int Months(DateTime dt1,DateTime dt2)
{
if (dt2<dt1)
{
DateTime dt0=dt1;
dt1=dt2;
dt2=dt0;
}
dt2=dt2.AddDays(-(dt1.Day-1));
return (dt2.Year-dt1.Year)*12+(dt2.Month-dt1.Month);
}
/// <summary>
/// Returns the higher of the two date time values.
/// </summary>
/// <param name="dt1">The first of the two <c>DateTime</c> values to compare.</param>
/// <param name="dt2">The second of the two <c>DateTime</c> values to compare.</param>
/// <returns><c>dt1</c> or <c>dt2</c>, whichever is higher.</returns>
public static DateTime Max(DateTime dt1,DateTime dt2)
{
return (dt2>dt1?dt2:dt1);
}
/// <summary>
/// Returns the lower of the two date time values.
/// </summary>
/// <param name="dt1">The first of the two <c>DateTime</c> values to compare.</param>
/// <param name="dt2">The second of the two <c>DateTime</c> values to compare.</param>
/// <returns><c>dt1</c> or <c>dt2</c>, whichever is lower.</returns>
public static DateTime Min(DateTime dt1,DateTime dt2)
{
return (dt2<dt1?dt2:dt1);
}
/// <summary>
/// Adds the given number of business days to the <see cref="DateTime"/>.
/// </summary>
/// <param name="current">The date to be changed.</param>
/// <param name="days">Number of business days to be added.</param>
/// <param name="holidays">An optional list of holiday (non-business) days to consider.</param>
/// <returns>A <see cref="DateTime"/> increased by a given number of business days.</returns>
public static DateTime AddBusinessDays(
this DateTime current,
int days,
IEnumerable<DateTime> holidays = null)
{
var sign = Math.Sign(days);
var unsignedDays = Math.Abs(days);
for (var i = 0; i < unsignedDays; i++)
{
do
{
current = current.AddDays(sign);
}
while (current.DayOfWeek == DayOfWeek.Saturday
|| current.DayOfWeek == DayOfWeek.Sunday
|| (holidays != null && holidays.Contains(current.Date))
);
}
return current;
}
/// <summary>
/// Subtracts the given number of business days to the <see cref="DateTime"/>.
/// </summary>
/// <param name="current">The date to be changed.</param>
/// <param name="days">Number of business days to be subtracted.</param>
/// <param name="holidays">An optional list of holiday (non-business) days to consider.</param>
/// <returns>A <see cref="DateTime"/> increased by a given number of business days.</returns>
public static DateTime SubtractBusinessDays(
this DateTime current,
int days,
IEnumerable<DateTime> holidays)
{
return AddBusinessDays(current, -days, holidays);
}
/// <summary>
/// Retrieves the number of business days from two dates
/// </summary>
/// <param name="startDate">The inclusive start date</param>
/// <param name="endDate">The inclusive end date</param>
/// <param name="holidays">An optional list of holiday (non-business) days to consider.</param>
/// <returns></returns>
public static int GetBusinessDays(
this DateTime startDate,
DateTime endDate,
IEnumerable<DateTime> holidays)
{
if (startDate > endDate)
throw new NotSupportedException("ERROR: [startDate] cannot be greater than [endDate].");
int cnt = 0;
for (var current = startDate; current < endDate; current = current.AddDays(1))
{
if (current.DayOfWeek == DayOfWeek.Saturday
|| current.DayOfWeek == DayOfWeek.Sunday
|| (holidays != null && holidays.Contains(current.Date))
)
{
// skip holiday
}
else cnt++;
}
return cnt;
}
/// <summary>
/// Calculate Easter Sunday for any given year.
/// src.: https://stackoverflow.com/a/2510411/1233379
/// </summary>
/// <param name="year">The year to calcolate Easter against.</param>
/// <returns>a DateTime object containing the Easter month and day for the given year</returns>
public static DateTime GetEasterSunday(int year)
{
int day = 0;
int month = 0;
int g = year % 19;
int c = year / 100;
int h = (c - (int)(c / 4) - (int)((8 * c + 13) / 25) + 19 * g + 15) % 30;
int i = h - (int)(h / 28) * (1 - (int)(h / 28) * (int)(29 / (h + 1)) * (int)((21 - g) / 11));
day = i - ((year + (int)(year / 4) + i + 2 - c + (int)(c / 4)) % 7) + 28;
month = 3;
if (day > 31)
{
month++;
day -= 31;
}
return new DateTime(year, month, day);
}
/// <summary>
/// Retrieve holidays for given years
/// </summary>
/// <param name="years">an array of years to retrieve the holidays</param>
/// <param name="countryCode">a country two letter ISO (ex.: "IT") to add the holidays specific for that country</param>
/// <param name="cityName">a city name to add the holidays specific for that city</param>
/// <returns></returns>
public static IEnumerable<DateTime> GetHolidays(IEnumerable<int> years, string countryCode = null, string cityName = null)
{
var lst = new List<DateTime>();
foreach (var year in years.Distinct())
{
lst.AddRange(new[] {
new DateTime(year, 1, 1), // 1 gennaio (capodanno)
new DateTime(year, 1, 6), // 6 gennaio (epifania)
new DateTime(year, 5, 1), // 1 maggio (lavoro)
new DateTime(year, 8, 15), // 15 agosto (ferragosto)
new DateTime(year, 11, 1), // 1 novembre (ognissanti)
new DateTime(year, 12, 8), // 8 dicembre (immacolata concezione)
new DateTime(year, 12, 25), // 25 dicembre (natale)
new DateTime(year, 12, 26) // 26 dicembre (s. stefano)
});
// add easter sunday (pasqua) and monday (pasquetta)
var easterDate = GetEasterSunday(year);
lst.Add(easterDate);
lst.Add(easterDate.AddDays(1));
// country-specific holidays
if (!String.IsNullOrEmpty(countryCode))
{
switch (countryCode.ToUpper())
{
case "IT":
lst.Add(new DateTime(year, 4, 25)); // 25 aprile (liberazione)
break;
case "US":
lst.Add(new DateTime(year, 7, 4)); // 4 luglio (Independence Day)
break;
// todo: add other countries
case default:
// unsupported country: do nothing
break;
}
}
// city-specific holidays
if (!String.IsNullOrEmpty(cityName))
{
switch (cityName)
{
case "Rome":
case "Roma":
lst.Add(new DateTime(year, 6, 29)); // 29 giugno (s. pietro e paolo)
break;
case "Milano":
case "Milan":
lst.Add(new DateTime(year, 12, 7)); // 7 dicembre (s. ambrogio)
break;
// todo: add other cities
default:
// unsupported city: do nothing
break;
}
}
}
return lst;
}
}
该代码非常不言自明，但是这里有几个示例来解释如何使用它。
添加 10 个工作日（仅跳过周六和周日工作日）
var dtResult = DateTimeUtil.AddBusinessDays(srcDate, 10);
添加 10 个工作日（跳过周六、周日以及 2019 年所有国家/地区不变的假期）
var dtResult = DateTimeUtil.AddBusinessDays(srcDate, 10, GetHolidays(2019));
添加 10 个工作日（跳过周六、周日和 2019 年所有意大利假期）
var dtResult = DateTimeUtil.AddBusinessDays(srcDate, 10, GetHolidays(2019, "IT"));
添加 10 个工作日（跳过周六、周日、所有意大利假期和 2019 年罗马特定假期）
var dtResult = DateTimeUtil.AddBusinessDays(srcDate, 10, GetHolidays(2019, "IT", "Rome"));
有关其他信息和示例，请查看我博客的这篇文章。
也许有点太晚了，但你可以使用我的图书馆Nager.Date。通过我的库，您可以计算 100 多个不同国家/地区的假期。还有一个 nuget 包可用。
我知道这已经很老了，但它引导我走向正确的方向，我想发布我的代码。我需要为我正在开发的员工假期跟踪器获取假期，并在这个过程中发现复活节要求您计算春分和月亮周期。我为我的特定地区设置了假期，因为对于我的申请来说，这就是我所需要的。我发现的卫星计算结果足够近似，可以得到精确到小时的月相，您需要用三角学来计算月亮和太阳的位置，我认为这对于此目的来说是不必要的。
我在 GitHub 上找到的月相源代码。我尝试根据网上找到的一些公式示例创建自己的方法，但它会缩短一天。
public class Holiday
{
private DateTime? _date;
public DateTime? Date
{
get { return _date; }
set { _date = value; }
}
private DateTime? _inLieuDate;
public DateTime? InLieuDate
{
get { return _inLieuDate; }
set { _inLieuDate = value; }
}
private string _name;
public string Name
{
get { return _name; }
set { _name = value; }
}
public Holiday(string name, DateTime? date)
{
Date = date;
Name = name;
}
public Holiday(string name, DateTime? date, DateTime? inLieuDate)
{
Date = date;
Name = name;
InLieuDate = inLieuDate;
}
}
public static class LocalHolidays
{
public static List<Holiday> GetHolidays(int year)
{
List<Holiday> holidays = new List<Holiday> ();
// New Years
DateTime newYearsDate = new DateTime(year, 1, 1);
DateTime inLieunewYearsDate = AdjustForWeekendHoliday(newYearsDate);
holidays.Add(new Holiday("New Years Day",newYearsDate,inLieunewYearsDate));
// Family Day -- 3rd Monday in February
var _familyDay = (from day in Enumerable.Range(1, DateTime.DaysInMonth(year, 2))
where new DateTime(year, 2, day).DayOfWeek == DayOfWeek.Monday
select day).ElementAt(2);
DateTime familyDay = new DateTime(year, 2, _familyDay);
holidays.Add(new Holiday("Family Day", familyDay));
// Good Friday -- The friday before the first Sunday after the full Moon that occurs on or after the spring equinox
DateTime goodFriday = GetEasterSunday(year);
DayOfWeek dayOfWeek = goodFriday.DayOfWeek;
while (dayOfWeek != DayOfWeek.Friday)
{
goodFriday = goodFriday.AddDays(-1);
dayOfWeek = goodFriday.DayOfWeek;
}
holidays.Add(new Holiday("Good Friday", goodFriday));
// Victoria Day -- Monday before May 25th
DateTime victoriaDay = new DateTime(year, 5, 25);
dayOfWeek = victoriaDay.DayOfWeek;
while (dayOfWeek != DayOfWeek.Monday)
{
victoriaDay = victoriaDay.AddDays(-1);
dayOfWeek = victoriaDay.DayOfWeek;
}
holidays.Add(new Holiday("Victoria Day", victoriaDay));
// Canada Day
DateTime canadaDay = new DateTime(year, 7, 1);
DateTime inLieucanadaDay = AdjustForWeekendHoliday(canadaDay);
holidays.Add(new Holiday("Canada Day", canadaDay,inLieucanadaDay));
// Heritage Day -- 1st Monday in August
DateTime heritageDay = new DateTime(year, 8, 1);
dayOfWeek = heritageDay.DayOfWeek;
while (dayOfWeek != DayOfWeek.Monday)
{
heritageDay = heritageDay.AddDays(1);
dayOfWeek = heritageDay.DayOfWeek;
}
holidays.Add(new Holiday("Heritage Day", heritageDay));
// Labour Day -- 1st Monday in September
DateTime labourDay = new DateTime(year, 9, 1);
dayOfWeek = labourDay.DayOfWeek;
while (dayOfWeek != DayOfWeek.Monday)
{
labourDay = labourDay.AddDays(1);
dayOfWeek = labourDay.DayOfWeek;
}
holidays.Add(new Holiday("Labour Day", labourDay));
// Thanksgiving Day -- 2nd Monday in October
var thanksgiving = (from day in Enumerable.Range(1, DateTime.DaysInMonth(year, 10))
where new DateTime(year, 10, day).DayOfWeek == DayOfWeek.Monday
select day).ElementAt(1);
DateTime thanksgivingDay = new DateTime(year, 10, thanksgiving);
holidays.Add(new Holiday("Thanksgiving Day", thanksgivingDay));
// Remembrance Day
DateTime remembranceDay = new DateTime(year, 11, 11);
DateTime inLieuremembranceDay = AdjustForWeekendHoliday(remembranceDay);
holidays.Add(new Holiday("Remembrance Day", remembranceDay, inLieuremembranceDay));
// Christmas Day
DateTime christmasDay = new DateTime(year, 12, 25);
DateTime inLieuchristmasDay = AdjustForWeekendHoliday(christmasDay);
holidays.Add(new Holiday("Christmas Day", christmasDay, inLieuchristmasDay));
// Boxing Day
DateTime boxingDay = new DateTime(year, 12, 26);
DateTime inLieuBoxingDay = AdjustForWeekendHoliday(boxingDay);
holidays.Add(new Holiday("Boxing Day", boxingDay, inLieuBoxingDay));
return holidays;
}
public static DateTime AdjustForWeekendHoliday(DateTime holiday)
{
if (holiday.DayOfWeek == DayOfWeek.Saturday)
{
return holiday.AddDays(-1);
}
else if (holiday.DayOfWeek == DayOfWeek.Sunday)
{
return holiday.AddDays(1);
}
else
{
return holiday;
}
}
internal static DateTime GetEasterSunday(int year)
{
DateTime springEquinox = GetSpringEquinox(year);
Moon moon = new Moon();
DateTime foundDate = moon.GetNextFullMoon(springEquinox);
DayOfWeek dayOfWeek = foundDate.DayOfWeek;
while (dayOfWeek != DayOfWeek.Sunday)
{
foundDate = foundDate.AddDays(1);
dayOfWeek = foundDate.DayOfWeek;
}
return foundDate;
}
internal static DateTime GetSpringEquinox(int year)
{
int lastTwoDigits = year % 100;
int calculatedDate = (int)(((lastTwoDigits * 0.2422) + 20.646) - GetCurrentCententuryLeapYears(year));
DateTime foundDate = new DateTime(year, 3,calculatedDate);
return foundDate;
}
internal static int GetCurrentCententuryLeapYears(int year)
{
int leapCopunter = 0;
int century = Convert.ToInt32(Math.Floor(year / 100d))*100;
for(int i = century;i <= year;i++)
{
if ((i % 4 == 0 && i % 100 != 0) || (i % 400 == 0 && i % 100 == 0))
{
leapCopunter++;
}
}
return leapCopunter;
}
}
public class Moon
{
static double MoonCycleLength = 29.53058770576;
private List<MoonPhase> _moonPhases = new List<MoonPhase>();
public List<MoonPhase> GetMoonPhases
{
get { return _moonPhases; }
}
public class MoonPhase
{
public double FromAge;
public double ToAge;
public Phase PhaseOfMoon;
public MoonPhase(double fromAge,double toAge, Phase phase)
{
FromAge = fromAge;
ToAge = toAge;
PhaseOfMoon = phase;
}
public enum Phase
{
NewMoon,
FirstQuarter,
FullMoon,
LastQuater
}
}
public Moon()
{
_moonPhases.Add(new MoonPhase(0,1,MoonPhase.Phase.NewMoon));
_moonPhases.Add(new MoonPhase((MoonCycleLength / 4)-1, (MoonCycleLength / 4) + 1, MoonPhase.Phase.FirstQuarter));
_moonPhases.Add(new MoonPhase((MoonCycleLength / 2)-1, (MoonCycleLength / 2) + 1, MoonPhase.Phase.FullMoon));
_moonPhases.Add(new MoonPhase((MoonCycleLength * .75)-1, (MoonCycleLength * .75) + 1, MoonPhase.Phase.LastQuater));
_moonPhases.Add(new MoonPhase(MoonCycleLength-1,MoonCycleLength, MoonPhase.Phase.NewMoon));
}
public int GetJulianDate(int day, int month, int year)
{
year = year - (12 - month) / 10;
month = month + 9;
if (month >= 12)
month = month - 12;
var k1 = (int)(365.25 * (year + 4712));
var k2 = (int)(30.6001 * month + 0.5);
// 'j' for dates in Julian calendar:
var julianDate = k1 + k2 + day + 59;
//Gregorian calendar
if (julianDate > 2299160)
{
var k3 = (int)((year / 100 + 49) * 0.75) - 38;
julianDate = julianDate - k3; //at 12h UT (Universal Time)
}
return julianDate;
}
public double GetMoonAge(DateTime fromDate)
{
int day = fromDate.Day;
int month = fromDate.Month;
int year = fromDate.Year;
double ip, age;
int julianDate = GetJulianDate(day, month, year);
ip = (julianDate + 4.867) / MoonCycleLength;
ip = ip - Math.Floor(ip);
age = ip * MoonCycleLength + MoonCycleLength / 2;
if (age > MoonCycleLength)
age -= MoonCycleLength;
return age;
}
public DateTime GetNextFullMoon(DateTime fromDate)
{
DateTime foundDate = fromDate;
while (!GetMoonAge(foundDate).IsBetween( GetMoonPhases.Where(x => x.PhaseOfMoon == MoonPhase.Phase.FullMoon).FirstOrDefault().FromAge, GetMoonPhases.Where(x => x.PhaseOfMoon == MoonPhase.Phase.FullMoon).FirstOrDefault().ToAge))
{
foundDate = foundDate.AddDays(1);
}
return foundDate;
}
}
public static class CompareValues
{
public static bool IsBetween(this double item, double start, double end)
{
return Comparer<double>.Default.Compare(item, start) >= 0
&& Comparer<double>.Default.Compare(item, end) <= 0;
}
}
public double GetMoonAge(DateTime fromDate)
{
int day = fromDate.Day;
int month = fromDate.Month;
int year = fromDate.Year;
if (month == 1 || month == 2)
{
year = year - 1;
month = month + 12;
}
double A = Math.Floor(year / 100d);
double B = Math.Floor(A / 4d);
double C = 2 - A + B;
double E = Math.Floor(365.25d * (year + 4716));
double F = Math.Floor(30.6001d * (month + 1));
double JD = C + day + E + F - 1524.5;
double DaysSinceNew = JD - 2451549.5;
double newMoons = DaysSinceNew / MoonCycleLength;
double age = (newMoons - Math.Truncate(newMoons)) * MoonCycleLength;
return age;
}
var publicHolidays = LocalHolidays.GetHolidays(2024);
foreach (Holiday publicHoliday in publicHolidays)
{
Console.WriteLine(publicHoliday.Name + " " + publicHoliday.Date.ToString() + " " + publicHoliday.InLieuDate.ToString());
}