public long DateDiff(c.DateInterval intervalType, DateTime dateOne, DateTime dateTwo)
{
switch (intervalType)
{
case c.DateInterval.Day:
case c.DateInterval.DayOfYear:
TimeSpan spanForDays = dateTwo - dateOne;
return((long)spanForDays.TotalDays);
case c.DateInterval.Hour:
TimeSpan spanForHours = dateTwo - dateOne;
return((long)spanForHours.TotalHours);
case c.DateInterval.Minute:
TimeSpan spanForMinutes = dateTwo - dateOne;
return((long)spanForMinutes.TotalMinutes);
case c.DateInterval.Month:
return(((dateTwo.Year - dateOne.Year) * 12) + (dateTwo.Month - dateOne.Month));
case c.DateInterval.Quarter:
long dateOneQuarter = (long)Math.Ceiling(dateOne.Month / 3.0);
long dateTwoQuarter = (long)Math.Ceiling(dateTwo.Month / 3.0);
return((4 * (dateTwo.Year - dateOne.Year)) + dateTwoQuarter - dateOneQuarter);
case c.DateInterval.Second:
TimeSpan spanForSeconds = dateTwo - dateOne;
return((long)spanForSeconds.TotalSeconds);
case c.DateInterval.Weekday:
TimeSpan spanForWeekdays = dateTwo - dateOne;
return((long)(spanForWeekdays.TotalDays / 7.0));
case c.DateInterval.WeekOfYear:
DateTime dateOneModified = dateOne;
DateTime dateTwoModified = dateTwo;
while (dateTwoModified.DayOfWeek != DateTimeFormatInfo.CurrentInfo.FirstDayOfWeek)
{
dateTwoModified = dateTwoModified.AddDays(-1);
}
while (dateOneModified.DayOfWeek != DateTimeFormatInfo.CurrentInfo.FirstDayOfWeek)
{
dateOneModified = dateOneModified.AddDays(-1);
}
TimeSpan spanForWeekOfYear = dateTwoModified - dateOneModified;
return((long)(spanForWeekOfYear.TotalDays / 7.0));
case c.DateInterval.Year:
return(dateTwo.Year - dateOne.Year);
default:
return(0);
}
}
public long DateDiff(c.DateInterval intervalType, string sDateOne, string sDateTwo)
{
DateTime t1;
DateTime t2;
if (!IsDate2(sDateOne) || !IsDate2(sDateTwo))
{
return(0);
}
t1 = StringToDate(sDateOne);
t2 = StringToDate(sDateTwo);
return(DateDiff(intervalType, t1, t2));
}
