JulianCalendar.AddYears(DateTime, Int32) Method

Reference

Definition

Namespace:: System.Globalization

Assemblies:: mscorlib.dll, System.Globalization.Calendars.dll

Assembly:: System.Runtime.dll

Assembly:: System.Globalization.Calendars.dll

Assembly:: mscorlib.dll

Assembly:: netstandard.dll

Source:: JulianCalendar.cs

Source:: JulianCalendar.cs

Source:: JulianCalendar.cs

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Returns a DateTime that is the specified number of years away from the specified DateTime.

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 DateTime to which to add years.

years: Int32

The number of years to add.

Returns

DateTime

The DateTime that results from adding the specified number of years to the specified DateTime.

Exceptions

ArgumentException

The resulting DateTime is outside the supported range.

Examples

The following code example displays the values of several components of a DateTime in terms of the Julian calendar.

using namespace System;
using namespace System::Globalization;
void DisplayValues( Calendar^ myCal, DateTime myDT )
{
   Console::WriteLine( "   Era:        {0}", myCal->GetEra( myDT ) );
   Console::WriteLine( "   Year:       {0}", myCal->GetYear( myDT ) );
   Console::WriteLine( "   Month:      {0}", myCal->GetMonth( myDT ) );
   Console::WriteLine( "   DayOfYear:  {0}", myCal->GetDayOfYear( myDT ) );
   Console::WriteLine( "   DayOfMonth: {0}", myCal->GetDayOfMonth( myDT ) );
   Console::WriteLine( "   DayOfWeek:  {0}", myCal->GetDayOfWeek( myDT ) );
   Console::WriteLine();
}

int main()
{
   
   // Sets a DateTime to April 3, 2002 of the Gregorian calendar.
   DateTime myDT = DateTime(2002,4,3,gcnew GregorianCalendar);
   
   // Creates an instance of the JulianCalendar.
   JulianCalendar^ myCal = gcnew JulianCalendar;
   
   // Displays the values of the DateTime.
   Console::WriteLine( "April 3, 2002 of the Gregorian calendar equals the following in the Julian calendar:" );
   DisplayValues( myCal, myDT );
   
   // Adds two years and ten months.
   myDT = myCal->AddYears( myDT, 2 );
   myDT = myCal->AddMonths( myDT, 10 );
   
   // Displays the values of the DateTime.
   Console::WriteLine( "After adding two years and ten months:" );
   DisplayValues( myCal, myDT );
}

/*
This code produces the following output.

April 3, 2002 of the Gregorian calendar equals the following in the Julian calendar:
   Era:        1
   Year:       2002
   Month:      3
   DayOfYear:  80
   DayOfMonth: 21
   DayOfWeek:  Wednesday

After adding two years and ten months:
   Era:        1
   Year:       2005
   Month:      1
   DayOfYear:  21
   DayOfMonth: 21
   DayOfWeek:  Thursday

*/

using System;
using System.Globalization;

public class SamplesJulianCalendar  {

   public static void Main()  {

      // Sets a DateTime to April 3, 2002 of the Gregorian calendar.
      DateTime myDT = new DateTime( 2002, 4, 3, new GregorianCalendar() );

      // Creates an instance of the JulianCalendar.
      JulianCalendar myCal = new JulianCalendar();

      // Displays the values of the DateTime.
      Console.WriteLine( "April 3, 2002 of the Gregorian calendar equals the following in the Julian calendar:" );
      DisplayValues( myCal, myDT );

      // Adds two years and ten months.
      myDT = myCal.AddYears( myDT, 2 );
      myDT = myCal.AddMonths( myDT, 10 );

      // Displays the values of the DateTime.
      Console.WriteLine( "After adding two years and ten months:" );
      DisplayValues( myCal, myDT );
   }

   public static void DisplayValues( Calendar myCal, DateTime myDT )  {
      Console.WriteLine( "   Era:        {0}", myCal.GetEra( myDT ) );
      Console.WriteLine( "   Year:       {0}", myCal.GetYear( myDT ) );
      Console.WriteLine( "   Month:      {0}", myCal.GetMonth( myDT ) );
      Console.WriteLine( "   DayOfYear:  {0}", myCal.GetDayOfYear( myDT ) );
      Console.WriteLine( "   DayOfMonth: {0}", myCal.GetDayOfMonth( myDT ) );
      Console.WriteLine( "   DayOfWeek:  {0}", myCal.GetDayOfWeek( myDT ) );
      Console.WriteLine();
   }
}

/*
This code produces the following output.

April 3, 2002 of the Gregorian calendar equals the following in the Julian calendar:
   Era:        1
   Year:       2002
   Month:      3
   DayOfYear:  80
   DayOfMonth: 21
   DayOfWeek:  Wednesday

After adding two years and ten months:
   Era:        1
   Year:       2005
   Month:      1
   DayOfYear:  21
   DayOfMonth: 21
   DayOfWeek:  Thursday

*/

Imports System.Globalization


Public Class SamplesJulianCalendar   

   Public Shared Sub Main()

      ' Sets a DateTime to April 3, 2002 of the Gregorian calendar.
      Dim myDT As New DateTime(2002, 4, 3, New GregorianCalendar())

      ' Creates an instance of the JulianCalendar.
      Dim myCal As New JulianCalendar()

      ' Displays the values of the DateTime.
      Console.WriteLine("April 3, 2002 of the Gregorian calendar equals the following in the Julian calendar:")
      DisplayValues(myCal, myDT)

      ' Adds two years and ten months.
      myDT = myCal.AddYears(myDT, 2)
      myDT = myCal.AddMonths(myDT, 10)

      ' Displays the values of the DateTime.
      Console.WriteLine("After adding two years and ten months:")
      DisplayValues(myCal, myDT)

   End Sub

   Public Shared Sub DisplayValues(myCal As Calendar, myDT As DateTime)
      Console.WriteLine("   Era:        {0}", myCal.GetEra(myDT))
      Console.WriteLine("   Year:       {0}", myCal.GetYear(myDT))
      Console.WriteLine("   Month:      {0}", myCal.GetMonth(myDT))
      Console.WriteLine("   DayOfYear:  {0}", myCal.GetDayOfYear(myDT))
      Console.WriteLine("   DayOfMonth: {0}", myCal.GetDayOfMonth(myDT))
      Console.WriteLine("   DayOfWeek:  {0}", myCal.GetDayOfWeek(myDT))
      Console.WriteLine()
   End Sub

End Class


'This code produces the following output.
'
'April 3, 2002 of the Gregorian calendar equals the following in the Julian calendar:
'   Era:        1
'   Year:       2002
'   Month:      3
'   DayOfYear:  80
'   DayOfMonth: 21
'   DayOfWeek:  Wednesday
'
'After adding two years and ten months:
'   Era:        1
'   Year:       2005
'   Month:      1
'   DayOfYear:  21
'   DayOfMonth: 21
'   DayOfWeek:  Thursday

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, ArgumentException 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, February has 28 days, except during leap years when it has 29 days. If the specified date is the 29th day of February in a leap year and the value of years is 1, the resulting date is the 28th day of February 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

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