GregorianCalendar.IsLeapMonth Method (Int32, Int32, Int32)

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Determines whether the specified month in the specified year in the specified era is a leap month.

Namespace:  System.Globalization
Assembly:  mscorlib (in mscorlib.dll)

Syntax

'Declaration
Public Overrides Function IsLeapMonth ( _
    year As Integer, _
    month As Integer, _
    era As Integer _
) As Boolean
public override bool IsLeapMonth(
    int year,
    int month,
    int era
)

Parameters

  • year
    Type: System.Int32
    An integer that represents the year.
  • month
    Type: System.Int32
    An integer from 1 to 12 that represents the month.
  • era
    Type: System.Int32
    An integer that represents the era.

Return Value

Type: System.Boolean
This method always returns false, unless overridden by a derived class.

Exceptions

Exception Condition
ArgumentOutOfRangeException

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.

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 month is an entire month that occurs only in a leap year. The Gregorian calendar does not have any leap months.

Examples

The following code example calls IsLeapMonth for all the months in five years in the current era.

Imports System.Globalization

Public Class Example
   Public Shared Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)
      ' Creates and initializes a GregorianCalendar.
      Dim myCal As New GregorianCalendar()

      ' Checks all the months in five years in the current era.
      Dim iMonthsInYear As Integer
      For y As Integer = 2001 To 2005
         outputBlock.Text += String.Format("{0}:" + ControlChars.Tab, y)
         iMonthsInYear = myCal.GetMonthsInYear(y, GregorianCalendar.CurrentEra)
         For m As Integer = 1 To iMonthsInYear
            outputBlock.Text += String.Format(ControlChars.Tab + "{0}", myCal.IsLeapMonth(y, m, GregorianCalendar.CurrentEra))
         Next 
         outputBlock.Text &= vbCrLf
      Next 
   End Sub 
End Class 
' This example produces the following output.
' 2001:           False   False   False   False   False   False   False   False   False   False   False   False
' 2002:           False   False   False   False   False   False   False   False   False   False   False   False
' 2003:           False   False   False   False   False   False   False   False   False   False   False   False
' 2004:           False   False   False   False   False   False   False   False   False   False   False   False
' 2005:           False   False   False   False   False   False   False   False   False   False   False   False
using System;
using System.Globalization;


public class Example
{

   public static void Demo(System.Windows.Controls.TextBlock outputBlock)
   {

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

      // Checks all the months in five years in the current era.
      int iMonthsInYear;
      for (int y = 2001; y <= 2005; y++)
      {
         outputBlock.Text += String.Format("{0}:\t", y);
         iMonthsInYear = myCal.GetMonthsInYear(y, GregorianCalendar.CurrentEra);
         for (int m = 1; m <= iMonthsInYear; m++)
            outputBlock.Text += String.Format("\t{0}", myCal.IsLeapMonth(y, m, GregorianCalendar.CurrentEra));
         outputBlock.Text += "\n";
      }

   }

}

/*
This code produces the following output.

2001:           False   False   False   False   False   False   False   False   False   False   False   False
2002:           False   False   False   False   False   False   False   False   False   False   False   False
2003:           False   False   False   False   False   False   False   False   False   False   False   False
2004:           False   False   False   False   False   False   False   False   False   False   False   False
2005:           False   False   False   False   False   False   False   False   False   False   False   False

*/

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.