UmAlQuraCalendar.AddYears(DateTime, Int32) Method

Definition

Calculates a date that is a specified number of years away from a specified initial date.

public:
 override DateTime AddYears(DateTime time, int years);
public override DateTime AddYears (DateTime time, int years);
override this.AddYears : DateTime * int -> DateTime
Public Overrides Function AddYears (time As DateTime, years As Integer) As DateTime

Parameters

time
DateTime

The date to which to add years. The UmAlQuraCalendar class supports only dates from 04/30/1900 00.00.00 (Gregorian date) through 11/16/2077 23:59:59 (Gregorian date).

years
Int32

The positive or negative number of years to add.

Returns

The date yielded by adding the number of years specified by the years parameter to the date specified by the time parameter.

Exceptions

The resulting date is outside the range supported by the UmAlQuraCalendar class.

years is less than -10,000 or greater than 10,000.

-or-

time is outside the range supported by this calendar.

Examples

The following example instantiates a DateTime value and displays the values of several of its components in the Um AL Qura calendar. Next, it calls the AddYears and AddMonths methods to add 2 years and 10 months in the Um Al Qura calendar to the date value. Finally, it again displays the values of these date components in the Um Al Qura calendar.

using System;
using System.Globalization;

public class Example
{
   public static void Main()
   {
      DateTime date1 = new DateTime(2011, 4, 3, new GregorianCalendar());
      Calendar cal = new UmAlQuraCalendar();
      
      Console.WriteLine("{0:MMMM d, yyyy} in the Gregorian calendar is equivalent to:", date1);
      DisplayCalendarInfo(cal, date1);
            
      // Add 2 years and 10 months by calling UmAlQuraCalendar methods.
      date1 = cal.AddYears(date1, 2);
      date1 = cal.AddMonths(date1, 10);       

      Console.WriteLine("After adding 2 years and 10 months in the {0} calendar,", 
                        GetCalendarName(cal));
      Console.WriteLine("{0:MMMM d, yyyy} in the Gregorian calendar is equivalent to:", date1);
      DisplayCalendarInfo(cal, date1);
   }

   private static void DisplayCalendarInfo(Calendar cal, DateTime date1)
   {
      Console.WriteLine("   Calendar:   {0}", GetCalendarName(cal));    
      Console.WriteLine("   Era:        {0}", cal.GetEra(date1));
      Console.WriteLine("   Year:       {0}", cal.GetYear(date1));
      Console.WriteLine("   Month:      {0}", cal.GetMonth(date1));
      Console.WriteLine("   DayOfYear:  {0}", cal.GetDayOfYear(date1));
      Console.WriteLine("   DayOfMonth: {0}", cal.GetDayOfMonth(date1));
      Console.WriteLine("   DayOfWeek:  {0}\n", cal.GetDayOfWeek(date1));
   }

   private static string GetCalendarName(Calendar cal)
   {
      return cal.ToString().Replace("System.Globalization.", "").
             Replace("Calendar", "");   
   }
}
// The example displays the following output:
//    April 3, 2011 in the Gregorian calendar is equivalent to:
//       Calendar:   UmAlQura
//       Era:        1
//       Year:       1432
//       Month:      4
//       DayOfYear:  118
//       DayOfMonth: 29
//       DayOfWeek:  Sunday
//    
//    After adding 2 years and 10 months in the UmAlQura calendar,
//    January 1, 2014 in the Gregorian calendar is equivalent to:
//       Calendar:   UmAlQura
//       Era:        1
//       Year:       1435
//       Month:      2
//       DayOfYear:  59
//       DayOfMonth: 29
//       DayOfWeek:  Wednesday
Imports System.Globalization

Module Example
   Public Sub Main()
      Dim date1 As Date = New Date(2011, 4, 3, New GregorianCalendar())
      Dim cal As New UmAlQuraCalendar()
      
      Console.WriteLine("{0:MMMM d, yyyy} in the Gregorian calendar is equivalent to:", date1)
      DisplayCalendarInfo(cal, date1)
            
      ' Add 2 years and 10 months by calling UmAlQuraCalendar methods.
      date1 = cal.AddYears(date1, 2)
      date1 = cal.AddMonths(date1, 10)       

      Console.WriteLine("After adding 2 years and 10 months in the {0} calendar,", 
                        GetCalendarName(cal))
      Console.WriteLine("{0:MMMM d, yyyy} in the Gregorian calendar is equivalent to:", date1)
      DisplayCalendarInfo(cal, date1)
   End Sub
   
   Private Sub DisplayCalendarInfo(cal As Calendar, date1 As Date)
      Console.WriteLine("   Calendar:   {0}", GetCalendarName(cal))    
      Console.WriteLine("   Era:        {0}", cal.GetEra(date1))
      Console.WriteLine("   Year:       {0}", cal.GetYear(date1))
      Console.WriteLine("   Month:      {0}", cal.GetMonth(date1))
      Console.WriteLine("   DayOfYear:  {0}", cal.GetDayOfYear(date1))
      Console.WriteLine("   DayOfMonth: {0}", cal.GetDayOfMonth(date1))
      Console.WriteLine("   DayOfWeek:  {0}", cal.GetDayOfWeek(date1))
      Console.WriteLine()
   End Sub
   
   Private Function GetCalendarName(cal As Calendar) As String
      Return cal.ToString().Replace("System.Globalization.", "").
             Replace("Calendar", "")   
   End Function
End Module
' The example displays the following output:
'    April 3, 2011 in the Gregorian calendar is equivalent to:
'       Calendar:   UmAlQura
'       Era:        1
'       Year:       1432
'       Month:      4
'       DayOfYear:  118
'       DayOfMonth: 29
'       DayOfWeek:  Sunday
'    
'    After adding 2 years and 10 months in the UmAlQura calendar,
'    January 1, 2014 in the Gregorian calendar is equivalent to:
'       Calendar:   UmAlQura
'       Era:        1
'       Year:       1435
'       Month:      2
'       DayOfYear:  59
'       DayOfMonth: 29
'       DayOfWeek:  Wednesday

Remarks

The day part of the resulting DateTime is affected if the resulting day is not a valid day in the resulting month of the resulting year. It is changed to the last valid day in the resulting month of the resulting year. The month part of the resulting DateTime remains the same as the specified DateTime. This implementation supports only the current era. Therefore, an exception is thrown if the resulting year is outside the era of the specified DateTime. The time-of-day part of the resulting DateTime remains the same as the specified DateTime.

For example, Zulhijjah has 29 days, except during leap years when it has 30 days. If the specified date is the 30th day of Zulhijjah in a leap year and the value of the years parameter is 1, the resulting date is the 29th day of Zulhijjah in the following year.

If years is negative, the resulting DateTime is earlier than the specified DateTime.

The Kind property of the returned DateTime value always equals DateTimeKind.Unspecified. You can preserve the Kind property of the time parameter by calling the DateTime.SpecifyKind method, as the following example shows.

returnTime = DateTime.SpecifyKind(cal.AddYears(time, years), time.Kind);
returnTime = DateTime.SpecifyKind(cal.AddYears(time, years), time.Kind)

Applies to