JapaneseCalendar.AddMonths(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:: JapaneseCalendar.cs

Source:: JapaneseCalendar.cs

Source:: JapaneseCalendar.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 months away from the specified DateTime.

public:
 override DateTime AddMonths(DateTime time, int months);

public override DateTime AddMonths (DateTime time, int months);

override this.AddMonths : DateTime * int -> DateTime

Public Overrides Function AddMonths (time As DateTime, months As Integer) As DateTime

Parameters

time: DateTime

The DateTime to which to add months.

months: Int32

The number of months to add.

Returns

DateTime

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

Exceptions

ArgumentException

The resulting DateTime is outside the supported range.

ArgumentOutOfRangeException

months is less than -120000.

-or-

months is greater than 120000.

Examples

The following code example displays the values of several components of a DateTime in terms of the Japanese 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 JapaneseCalendar.
   JapaneseCalendar^ myCal = gcnew JapaneseCalendar;
   
   // Displays the values of the DateTime.
   Console::WriteLine( "April 3, 2002 of the Gregorian calendar equals the following in the Japanese 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 Japanese calendar:
   Era:        4
   Year:       14
   Month:      4
   DayOfYear:  93
   DayOfMonth: 3
   DayOfWeek:  Wednesday

After adding two years and ten months:
   Era:        4
   Year:       17
   Month:      2
   DayOfYear:  34
   DayOfMonth: 3
   DayOfWeek:  Thursday

*/

using System;
using System.Globalization;

public class SamplesJapaneseCalendar  {

   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 JapaneseCalendar.
      JapaneseCalendar myCal = new JapaneseCalendar();

      // Displays the values of the DateTime.
      Console.WriteLine( "April 3, 2002 of the Gregorian calendar equals the following in the Japanese 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 Japanese calendar:
   Era:        4
   Year:       14
   Month:      4
   DayOfYear:  93
   DayOfMonth: 3
   DayOfWeek:  Wednesday

After adding two years and ten months:
   Era:        4
   Year:       17
   Month:      2
   DayOfYear:  34
   DayOfMonth: 3
   DayOfWeek:  Thursday

*/

Imports System.Globalization


Public Class SamplesJapaneseCalendar   

   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 JapaneseCalendar.
      Dim myCal As New JapaneseCalendar()

      ' Displays the values of the DateTime.
      Console.WriteLine("April 3, 2002 of the Gregorian calendar equals the following in the Japanese 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 Japanese calendar:
'   Era:        4
'   Year:       14
'   Month:      4
'   DayOfYear:  93
'   DayOfMonth: 3
'   DayOfWeek:  Wednesday
'
'After adding two years and ten months:
'   Era:        4
'   Year:       17
'   Month:      2
'   DayOfYear:  34
'   DayOfMonth: 3
'   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 year part of the resulting DateTime is affected if the resulting month is outside the year of the specified DateTime. The era part of the resulting DateTime is affected 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, if the specified month is Juugatsu (October), which has 31 days, the specified day is the 31st day of that month, and months is 6, the resulting year is one more than the specified year, the resulting month is Shigatsu (April), and the resulting day is the 30th day, which is the last day in Shigatsu (April).

If months 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.AddMonths(time, months), time.Kind);

returnTime = DateTime.SpecifyKind(cal.AddMonths(time, months), time.Kind)

Applies to

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