/// <summary>Returns a <see langword="Long" /> value specifying the number of time intervals between two <see langword="Date" /> values.</summary>
/// <param name="Interval">Required. <see langword="DateInterval" /> enumeration value or <see langword="String" /> expression representing the time interval you want to use as the unit of difference between <paramref name="Date1" /> and <paramref name="Date2" />.</param>
/// <param name="Date1">Required. <see langword="Date" />. The first date/time value you want to use in the calculation. </param>
/// <param name="Date2">Required. <see langword="Date" />. The second date/time value you want to use in the calculation.</param>
/// <param name="DayOfWeek">Optional. A value chosen from the <see langword="FirstDayOfWeek" /> enumeration that specifies the first day of the week. If not specified, <see langword="FirstDayOfWeek.Sunday" /> is used.</param>
/// <param name="WeekOfYear">Optional. A value chosen from the <see langword="FirstWeekOfYear" /> enumeration that specifies the first week of the year. If not specified, <see langword="FirstWeekOfYear.Jan1" /> is used.</param>
/// <returns>Returns a <see langword="Long" /> value specifying the number of time intervals between two <see langword="Date" /> values.</returns>
/// <exception cref="T:System.ArgumentException">Invalid <paramref name="Interval" />.</exception>
/// <exception cref="T:System.ArgumentException">
/// <paramref name="Date1" />, <paramref name="Date2" />, or <paramref name="DayofWeek" /> is out of range.</exception>
/// <exception cref="T:System.InvalidCastException">
/// <paramref name="Date1" /> or <paramref name="Date2" /> is of an invalid type.</exception>
public static long DateDiff(DateInterval Interval, DateTime Date1, DateTime Date2, FirstDayOfWeek DayOfWeek = FirstDayOfWeek.Sunday, FirstWeekOfYear WeekOfYear = FirstWeekOfYear.Jan1)
{
TimeSpan timeSpan = Date2.Subtract(Date1);
switch (Interval)
{
case DateInterval.Year:
Calendar currentCalendar1 = DateAndTime.CurrentCalendar;
return((long)checked (currentCalendar1.GetYear(Date2) - currentCalendar1.GetYear(Date1)));
case DateInterval.Quarter:
Calendar currentCalendar2 = DateAndTime.CurrentCalendar;
return((long)checked ((currentCalendar2.GetYear(Date2) - currentCalendar2.GetYear(Date1)) * 4 + unchecked (checked (currentCalendar2.GetMonth(Date2) - 1) / 3) - unchecked (checked (currentCalendar2.GetMonth(Date1) - 1) / 3)));
case DateInterval.Month:
Calendar currentCalendar3 = DateAndTime.CurrentCalendar;
return((long)checked ((currentCalendar3.GetYear(Date2) - currentCalendar3.GetYear(Date1)) * 12 + currentCalendar3.GetMonth(Date2) - currentCalendar3.GetMonth(Date1)));
case DateInterval.DayOfYear:
case DateInterval.Day:
return(checked ((long)Math.Round(Conversion.Fix(timeSpan.TotalDays))));
case DateInterval.WeekOfYear:
Date1 = Date1.AddDays((double)checked (-DateAndTime.GetDayOfWeek(Date1, DayOfWeek)));
Date2 = Date2.AddDays((double)checked (-DateAndTime.GetDayOfWeek(Date2, DayOfWeek)));
return(checked ((long)Math.Round(Conversion.Fix(Date2.Subtract(Date1).TotalDays))) / 7L);
case DateInterval.Weekday:
return(checked ((long)Math.Round(Conversion.Fix(timeSpan.TotalDays))) / 7L);
case DateInterval.Hour:
return(checked ((long)Math.Round(Conversion.Fix(timeSpan.TotalHours))));
case DateInterval.Minute:
return(checked ((long)Math.Round(Conversion.Fix(timeSpan.TotalMinutes))));
case DateInterval.Second:
return(checked ((long)Math.Round(Conversion.Fix(timeSpan.TotalSeconds))));
default:
throw new ArgumentException(Utils.GetResourceString("Argument_InvalidValue1", new string[1]
{
nameof(Interval)
}));
}
}
/// <summary>Returns an <see langword="Integer" /> value containing the specified component of a given <see langword="Date" /> value.</summary>
/// <param name="Interval">Required. <see langword="DateInterval" /> enumeration value or <see langword="String" /> expression representing the part of the date/time value you want to return.</param>
/// <param name="DateValue">Required. <see langword="Date" /> value that you want to evaluate.</param>
/// <param name="FirstDayOfWeekValue">Optional. A value chosen from the <see langword="FirstDayOfWeek" /> enumeration that specifies the first day of the week. If not specified, <see langword="FirstDayOfWeek.Sunday" /> is used.</param>
/// <param name="FirstWeekOfYearValue">Optional. A value chosen from the <see langword="FirstWeekOfYear" /> enumeration that specifies the first week of the year. If not specified, <see langword="FirstWeekOfYear.Jan1" /> is used.</param>
/// <returns>Returns an <see langword="Integer" /> value containing the specified component of a given <see langword="Date" /> value.</returns>
/// <exception cref="T:System.ArgumentException">
/// <paramref name="Interval" /> is not valid. </exception>
/// <exception cref="T:System.InvalidCastException">
/// <paramref name="DateValue" /> is not coercible to <see langword="Date" />.</exception>
public static int DatePart(DateInterval Interval, DateTime DateValue, FirstDayOfWeek FirstDayOfWeekValue = FirstDayOfWeek.Sunday, FirstWeekOfYear FirstWeekOfYearValue = FirstWeekOfYear.Jan1)
{
switch (Interval)
{
case DateInterval.Year:
return(DateAndTime.CurrentCalendar.GetYear(DateValue));
case DateInterval.Quarter:
return(checked (unchecked (checked (DateValue.Month - 1) / 3) + 1));
case DateInterval.Month:
return(DateAndTime.CurrentCalendar.GetMonth(DateValue));
case DateInterval.DayOfYear:
return(DateAndTime.CurrentCalendar.GetDayOfYear(DateValue));
case DateInterval.Day:
return(DateAndTime.CurrentCalendar.GetDayOfMonth(DateValue));
case DateInterval.WeekOfYear:
DayOfWeek firstDayOfWeek = FirstDayOfWeekValue != FirstDayOfWeek.System ? (DayOfWeek)(FirstDayOfWeekValue - 1) : Utils.GetCultureInfo().DateTimeFormat.FirstDayOfWeek;
CalendarWeekRule rule = CalendarWeekRule.FirstDay;
switch (FirstWeekOfYearValue)
{
case FirstWeekOfYear.System:
rule = Utils.GetCultureInfo().DateTimeFormat.CalendarWeekRule;
break;
case FirstWeekOfYear.Jan1:
rule = CalendarWeekRule.FirstDay;
break;
case FirstWeekOfYear.FirstFourDays:
rule = CalendarWeekRule.FirstFourDayWeek;
break;
case FirstWeekOfYear.FirstFullWeek:
rule = CalendarWeekRule.FirstFullWeek;
break;
}
return(DateAndTime.CurrentCalendar.GetWeekOfYear(DateValue, rule, firstDayOfWeek));
case DateInterval.Weekday:
return(DateAndTime.Weekday(DateValue, FirstDayOfWeekValue));
case DateInterval.Hour:
return(DateAndTime.CurrentCalendar.GetHour(DateValue));
case DateInterval.Minute:
return(DateAndTime.CurrentCalendar.GetMinute(DateValue));
case DateInterval.Second:
return(DateAndTime.CurrentCalendar.GetSecond(DateValue));
default:
throw new ArgumentException(Utils.GetResourceString("Argument_InvalidValue1", new string[1]
{
nameof(Interval)
}));
}
}
