GregorianCalendar.IsLeapDay(Int32, Int32, Int32, Int32) Method

Definition

Determines whether the specified date in the specified era is a leap day.

public:
 override bool IsLeapDay(int year, int month, int day, int era);
public override bool IsLeapDay (int year, int month, int day, int era);
override this.IsLeapDay : int * int * int * int -> bool
Public Overrides Function IsLeapDay (year As Integer, month As Integer, day As Integer, era As Integer) As Boolean

Parameters

year
Int32

An integer that represents the year.

month
Int32

An integer from 1 to 12 that represents the month.

day
Int32

An integer from 1 to 31 that represents the day.

era
Int32

An integer that represents the era.

Returns

true if the specified day is a leap day; otherwise, false.

Exceptions

era is outside the range supported by the calendar.

-or-

year is outside the range supported by the calendar.

-or-

month is outside the range supported by the calendar.

-or-

day is outside the range supported by the calendar.

Examples

The following code example calls IsLeapDay for the last day of the second month (February) for five years in each of the eras.

using namespace System;
using namespace System::Globalization;
int main()
{
   
   // Creates and initializes a GregorianCalendar.
   GregorianCalendar^ myCal = gcnew GregorianCalendar;
   
   // Creates a holder for the last day of the second month (February).
   int iLastDay;
   
   // Displays the header.
   Console::Write( "YEAR\t" );
   for ( int y = 2001; y <= 2005; y++ )
      Console::Write( "\t {0}", y );
   Console::WriteLine();
   
   // Checks five years in the current era.
   Console::Write( "CurrentEra:" );
   for ( int y = 2001; y <= 2005; y++ )
   {
      iLastDay = myCal->GetDaysInMonth( y, 2, GregorianCalendar::CurrentEra );
      Console::Write( "\t {0}", myCal->IsLeapDay( y, 2, iLastDay, GregorianCalendar::CurrentEra ) );

   }
   Console::WriteLine();
   
   // Checks five years in each of the eras.
   for ( int i = 0; i < myCal->Eras->Length; i++ )
   {
      Console::Write( "Era {0}:\t", myCal->Eras[ i ] );
      for ( int y = 2001; y <= 2005; y++ )
      {
         iLastDay = myCal->GetDaysInMonth( y, 2, myCal->Eras[ i ] );
         Console::Write( "\t {0}", myCal->IsLeapDay( y, 2, iLastDay, myCal->Eras[ i ] ) );

      }
      Console::WriteLine();

   }
}

/*
This code produces the following output.

YEAR            2001    2002    2003    2004    2005
CurrentEra:     False   False   False   True    False
Era 1:          False   False   False   True    False

*/
using System;
using System.Globalization;

public class SamplesGregorianCalendar  {

   public static void Main()  {

      // Creates and initializes a GregorianCalendar.
      GregorianCalendar myCal = new GregorianCalendar();

      // Creates a holder for the last day of the second month (February).
      int iLastDay;

      // Displays the header.
      Console.Write( "YEAR\t" );
      for ( int y = 2001; y <= 2005; y++ )
         Console.Write( "\t{0}", y );
      Console.WriteLine();

      // Checks five years in the current era.
      Console.Write( "CurrentEra:" );
      for ( int y = 2001; y <= 2005; y++ )  {
         iLastDay = myCal.GetDaysInMonth( y, 2, GregorianCalendar.CurrentEra );
         Console.Write( "\t{0}", myCal.IsLeapDay( y, 2, iLastDay, GregorianCalendar.CurrentEra ) );
      }
      Console.WriteLine();

      // Checks five years in each of the eras.
      for ( int i = 0; i < myCal.Eras.Length; i++ )  {
         Console.Write( "Era {0}:\t", myCal.Eras[i] );
         for ( int y = 2001; y <= 2005; y++ )  {
            iLastDay = myCal.GetDaysInMonth( y, 2, myCal.Eras[i] );
            Console.Write( "\t{0}", myCal.IsLeapDay( y, 2, iLastDay, myCal.Eras[i] ) );
         }
         Console.WriteLine();
      }
   }
}

/*
This code produces the following output.

YEAR            2001    2002    2003    2004    2005
CurrentEra:     False   False   False   True    False
Era 1:          False   False   False   True    False

*/
Imports System.Globalization

Public Class SamplesGregorianCalendar   
   
   Public Shared Sub Main()

      ' Creates and initializes a GregorianCalendar.
      Dim myCal As New GregorianCalendar()

      ' Creates a holder for the last day of the second month (February).
      Dim iLastDay As Integer

      ' Displays the header.
      Console.Write("YEAR" + ControlChars.Tab)
      Dim y As Integer
      For y = 2001 To 2005
         Console.Write(ControlChars.Tab + "{0}", y)
      Next y
      Console.WriteLine()

      ' Checks five years in the current era.
      Console.Write("CurrentEra:")
      For y = 2001 To 2005
         iLastDay = myCal.GetDaysInMonth(y, 2, GregorianCalendar.CurrentEra)
         Console.Write(ControlChars.Tab + "{0}", myCal.IsLeapDay(y, 2, iLastDay, GregorianCalendar.CurrentEra))
      Next y
      Console.WriteLine()

      ' Checks five years in each of the eras.
      Dim i As Integer
      For i = 0 To myCal.Eras.Length - 1
         Console.Write("Era {0}:" + ControlChars.Tab, myCal.Eras(i))
         For y = 2001 To 2005
            iLastDay = myCal.GetDaysInMonth(y, 2, myCal.Eras(i))
            Console.Write(ControlChars.Tab + "{0}", myCal.IsLeapDay(y, 2, iLastDay, myCal.Eras(i)))
         Next y
         Console.WriteLine()
      Next i

   End Sub

End Class


'This code produces the following output.
'
'YEAR            2001    2002    2003    2004    2005
'CurrentEra:     False   False   False   True    False
'Era 1:          False   False   False   True    False

Remarks

A leap year in the Gregorian calendar is defined as a year that is evenly divisible by four, except if it is divisible by 100. However, years that are divisible by 400 are leap years. For example, the year 1900 was not a leap year, but the year 2000 was. A common year has 365 days and a leap year has 366 days.

A leap day is a day that occurs only in a leap year. In the Gregorian calendar, the 29th day of February is the only leap day.

Applies to

See also