我意识到有类似的问题已被问到,但我觉得这些问题有不同的要求。
我需要检查当天是否是该月最后一个工作日的第N天或第N天。如果是,我开始另一项任务,否则我退出。
类似的东西:
void doTask()
{
if (NthFirstOrNthLastBusinessDay())
{ // do stuff }
else
{ // do nothing }
}
bool NthFirstOrNthLastBusinessDay()
{}
到目前为止,我认为我可以按照here的答案来获取该月的最后一个工作日(同样是该月的第一个工作日),然后应用一系列条件来计算第N个业务那天的那一天。
有更好的方法吗?
例如,如果N为4,我的任务应该只在今天是该月的第4个工作日或从该月的最后一个工作日的第4个工作日开始运行。
基本上,我每天都会调用此方法,它会检查当前是否满足此条件,如果是,则运行任务,否则它不会。
所以,我的任务应该在2014年7月28日和2014年8月6日以及2014年8月26日等等运行。
编辑: 这是我在N = 4时编写的一些代码:
/// <summary>
/// Checks if the current day is the 4th business day or the 4th last business day of the month
/// </summary>
/// <returns> True if current day satisfies condition, false otherwise </returns>
private bool NthFirstOrNthLastBusinessDay()
{
return (IsFourthBusinessDay() || IsFourthFromLastBusinessDay());
}
/// <summary>
/// Checks if today is the fourth business day of the month
/// </summary>
/// <returns> True if today satisfies condition, else false </returns>
private bool IsFourthBusinessDay()
{
var dateToday = DateTime.Today;
var firstDayOfThisMonth = new DateTime(dateToday.Year, dateToday.Month, 1);
switch (firstDayOfThisMonth.DayOfWeek)
{
case DayOfWeek.Sunday:
firstDayOfThisMonth = firstDayOfThisMonth.AddDays(4);
break;
case DayOfWeek.Monday:
firstDayOfThisMonth = firstDayOfThisMonth.AddDays(3);
break;
case DayOfWeek.Tuesday:
firstDayOfThisMonth = firstDayOfThisMonth.AddDays(3);
break;
default:
firstDayOfThisMonth = firstDayOfThisMonth.AddDays(5);
break;
} // firstDayOfMonth now contains first business day of month
return dateToday == firstDayOfThisMonth;
}
/// <summary>
/// Checks if today is the fourth from last business day of the month
/// </summary>
/// <returns> True if today satisfies condition, else false </returns>
private bool IsFourthFromLastBusinessDay()
{
var dateToday = DateTime.Today;
var lastDayOfThisMonth = new DateTime(dateToday.Year, dateToday.Month, DateTime.DaysInMonth(dateToday.Year, dateToday.Month));
switch (lastDayOfThisMonth.DayOfWeek)
{
case DayOfWeek.Saturday:
lastDayOfThisMonth = lastDayOfThisMonth.AddDays(-4);
break;
case DayOfWeek.Friday:
lastDayOfThisMonth = lastDayOfThisMonth.AddDays(-3);
break;
case DayOfWeek.Thursday:
lastDayOfThisMonth = lastDayOfThisMonth.AddDays(-3);
break;
default:
lastDayOfThisMonth = lastDayOfThisMonth.AddDays(-5);
break;
} // firstDayOfMonth now contains first business day of month
return dateToday == lastDayOfThisMonth;
}
现在我需要调整一般N的值。有更好的方法吗?
答案 0 :(得分:3)
根据对原始答案的OP评论,我决定将另一个函数作为练习。
这是(再次 - 未经过全面测试):
// Nth day should not be larger than 14 - I have tested it
bool Nth_BusinessDay(int NthDay, DateTime current)
{
// check we have NthDay larger than ZERO
if (NthDay < 1)
return false;
// make sure the taget date is just a date - no time component
DateTime target = current.Date;
// make sure the specialDay is not larger than the current days in the month
if (DateTime.DaysInMonth(target.Year, target.Month) > NthDay)
return false;
// start at the beginning
DateTime NthStart = new DateTime(target.Year, target.Month, 1);
// check if start date falls on the weekend
if (NthStart.DayOfWeek == DayOfWeek.Saturday)
NthStart = NthStart.AddDays(2); // jump TWO days to Monday
if (NthStart.DayOfWeek == DayOfWeek.Sunday)
NthStart = NthStart.AddDays(1); // jump ONE day to Monday
// now add our Nth day
NthStart = NthStart.AddDays(NthDay - 1);
// if we land on weekend after we adjusted for the Nth - push it by two days
if (NthStart.DayOfWeek == DayOfWeek.Saturday || NthStart.DayOfWeek == DayOfWeek.Sunday)
NthStart = NthStart.AddDays(2);
// start at the end and minus the Nth day
DateTime NthEnd = new DateTime(target.Year, target.Month, DateTime.DaysInMonth(target.Year, target.Month));
// check if the end date falls on the weekend - the difference here is the adjustment
if (NthEnd.DayOfWeek == DayOfWeek.Saturday)
NthEnd = NthEnd.AddDays(-1); // jump ONE day back to Friday
if (NthEnd.DayOfWeek == DayOfWeek.Sunday)
NthEnd = NthEnd.AddDays(-2); // jump TWO days back to Friday
// now subject our Nth day from the End
NthEnd = NthEnd.AddDays((NthDay - 1) * -1);
// again if we land on weekend - adjust by two days
if (NthStart.DayOfWeek == DayOfWeek.Saturday || NthStart.DayOfWeek == DayOfWeek.Sunday)
NthStart = NthStart.AddDays(2);
// check if our target day is one of the Nth day
if (NthStart == target || NthEnd == target)
return true;
return false;
}
并使用上述功能:
void doTaskNthDay()
{
if (Nth_BusinessDay(5, DateTime.Now))
{
// do stuff
}
}
以下是我在此留下的原始答案,仅供参考。
我从以下代码中获取了以下代码:.NET Date Compare: Count the amount of working days since a date?。 我还没有测试过这段代码,但您可以尝试这样的代码:
int BuinessDayCount(DateTime targetDay)
{
// check if the target day is a weekend
if (targetDay.DayOfWeek == DayOfWeek.Saturday)
return -1;
if (targetDay.DayOfWeek == DayOfWeek.Sunday)
return -2;
// get the start of the month
DateTime start = new DateTime(targetDay.Year, targetDay.Month, 1);
// create a target without any time component
DateTime end = targetDay.Date;
int workingDays = 0;
while (start <= targetDay)
{
if (start.DayOfWeek != DayOfWeek.Saturday
&& start.DayOfWeek != DayOfWeek.Sunday)
{
workingDays++;
}
start = start.AddDays(1);
}
return workingDays;
}
然后在你的代码中我会做以下几点:
void doTask()
{
int businessDay = BuinessDayCount(DateTime.Now);
if (businessDay == 5 || businessDay == 25)
{
// do stuff
}
}
我认为它会更好阅读。
答案 1 :(得分:0)
我会做类似的事情:
int numOfOccurredBusinessDays = 0; // this will include current business day
int businessDaysLeft = 0;
var currentDate = DateTime.Now;
var monthIterator = new DateTime(DateTime.Year, DateTime.Month, 1);
for (int i = 0; i < DateTime.DaysInMonth; ++i, monthIterator.AddDay(1))
{
if (monthIterator <= currentDate &&
!monthIterator.Date.ToString("D").Contains("Sat") &&
!monthIterator.Date.ToString("D").Contains("Sun"))
numOfOccurredBusinessDays++;
else if (monthIterator > currentDate &&
!monthIterator.Date.ToString("D").Contains("Sat") &&
!monthIterator.Date.ToString("D").Contains("Sun"))
businessDaysLeft++;
}
答案 2 :(得分:-1)
创建一个新的System.DateTime对象。使用当前年份和当前月份(可以从DateTime.Now获取)对其进行初始化。将日期设置为30(如果是9月/ 4月/ 6月/ 11月,或31,28等)
现在您有一个DateTime对象代表该月的最后一天。您可以使用DateTime.DayOfWeek来检查日期是星期六还是星期日(或假日)。
您可以使用DateTime.AddDays(-N)将DateTime对象“回退”一天,然后再次检查它是星期六或星期日(或假日)。
重复本月最后一天的任何一天检查你需要做的事。