Calendar.IsLeapDay Method (Int32, Int32, Int32)
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Determines whether the specified date in the current era is a leap day.
Namespace: System.Globalization
Assembly: mscorlib (in mscorlib.dll)
Syntax
'Declaration
Public Overridable Function IsLeapDay ( _
year As Integer, _
month As Integer, _
day As Integer _
) As Boolean
public virtual bool IsLeapDay(
int year,
int month,
int day
)
Parameters
- year
Type: System.Int32
An integer that represents the year.
- month
Type: System.Int32
A positive integer that represents the month.
- day
Type: System.Int32
A positive integer that represents the day.
Return Value
Type: System.Boolean
true if the specified day is a leap day; otherwise, false.
Exceptions
| Exception | Condition |
|---|---|
| ArgumentOutOfRangeException | 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. |
Remarks
To make up for the difference between the calendar year and the actual time that the earth rotates around the sun or the actual time that the moon rotates around the earth, a leap year has a different number of days from a standard calendar year. Each Calendar implementation defines leap years differently.
A leap day is a day that occurs only in a leap year. For example, in the Gregorian calendar, the 29th day of February is the only leap day.
Examples
The following code example compares different implementations of the Calendar class.
Imports System.Globalization
Public Class Example
Public Shared Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)
' Creates an instance of every Calendar type.
Dim myCals(6) As Calendar
myCals(0) = New GregorianCalendar()
myCals(1) = New HebrewCalendar()
myCals(2) = New HijriCalendar()
myCals(3) = New JapaneseCalendar()
myCals(4) = New KoreanCalendar()
myCals(5) = New TaiwanCalendar()
myCals(6) = New ThaiBuddhistCalendar()
' For each calendar, displays the current year, the number of months in that year,
' and the number of days in each month of that year.
Dim i, j, iYear, iMonth, iDay As Integer
Dim myDT As DateTime = DateTime.Today
For i = 0 To myCals.Length - 1
iYear = myCals(i).GetYear(myDT)
outputBlock.Text &= vbCrLf
outputBlock.Text += String.Format("{0}, Year: {1}", myCals(i).GetType(), myCals(i).GetYear(myDT)) & vbCrLf
outputBlock.Text += String.Format(" MonthsInYear: {0}", myCals(i).GetMonthsInYear(iYear)) & vbCrLf
outputBlock.Text += String.Format(" DaysInYear: {0}", myCals(i).GetDaysInYear(iYear)) & vbCrLf
outputBlock.Text &= " Days in each month:" & vbCrLf
outputBlock.Text &= " "
For j = 1 To myCals(i).GetMonthsInYear(iYear)
outputBlock.Text += String.Format(" {0,-5}", myCals(i).GetDaysInMonth(iYear, j))
Next j
outputBlock.Text &= vbCrLf
iMonth = myCals(i).GetMonth(myDT)
iDay = myCals(i).GetDayOfMonth(myDT)
outputBlock.Text += String.Format(" IsLeapDay: {0}", myCals(i).IsLeapDay(iYear, iMonth, iDay)) & vbCrLf
outputBlock.Text += String.Format(" IsLeapMonth: {0}", myCals(i).IsLeapMonth(iYear, iMonth)) & vbCrLf
outputBlock.Text += String.Format(" IsLeapYear: {0}", myCals(i).IsLeapYear(iYear)) & vbCrLf
Next
End Sub
End Class
'This code produces the following output. The results vary depending on the date.
'
' System.Globalization.GregorianCalendar, Year: 2002
' MonthsInYear: 12
' DaysInYear: 365
' Days in each month:
' 31 28 31 30 31 30 31 31 30 31 30 31
' IsLeapDay: False
' IsLeapMonth: False
' IsLeapYear: False
'
' System.Globalization.HebrewCalendar, Year: 5763
' MonthsInYear: 13
' DaysInYear: 385
' Days in each month:
' 30 30 30 29 30 30 29 30 29 30 29 30 29
' IsLeapDay: False
' IsLeapMonth: False
' IsLeapYear: True
'
' System.Globalization.HijriCalendar, Year: 1423
' MonthsInYear: 12
' DaysInYear: 355
' Days in each month:
' 30 29 30 29 30 29 30 29 30 29 30 30
' IsLeapDay: False
' IsLeapMonth: False
' IsLeapYear: True
'
' System.Globalization.JapaneseCalendar, Year: 14
' MonthsInYear: 12
' DaysInYear: 365
' Days in each month:
' 31 28 31 30 31 30 31 31 30 31 30 31
' IsLeapDay: False
' IsLeapMonth: False
' IsLeapYear: False
'
' System.Globalization.JulianCalendar, Year: 2002
' MonthsInYear: 12
' DaysInYear: 365
' Days in each month:
' 31 28 31 30 31 30 31 31 30 31 30 31
' IsLeapDay: False
' IsLeapMonth: False
' IsLeapYear: False
'
' System.Globalization.KoreanCalendar, Year: 4335
' MonthsInYear: 12
' DaysInYear: 365
' Days in each month:
' 31 28 31 30 31 30 31 31 30 31 30 31
' IsLeapDay: False
' IsLeapMonth: False
' IsLeapYear: False
'
' System.Globalization.TaiwanCalendar, Year: 91
' MonthsInYear: 12
' DaysInYear: 365
' Days in each month:
' 31 28 31 30 31 30 31 31 30 31 30 31
' IsLeapDay: False
' IsLeapMonth: False
' IsLeapYear: False
'
' System.Globalization.ThaiBuddhistCalendar, Year: 2545
' MonthsInYear: 12
' DaysInYear: 365
' Days in each month:
' 31 28 31 30 31 30 31 31 30 31 30 31
' IsLeapDay: False
' IsLeapMonth: False
' IsLeapYear: False
using System;
using System.Globalization;
public class Example
{
public static void Demo(System.Windows.Controls.TextBlock outputBlock)
{
// Creates an instance of every Calendar type.
Calendar[] myCals = new Calendar[7];
myCals[0] = new GregorianCalendar();
myCals[1] = new HebrewCalendar();
myCals[2] = new HijriCalendar();
myCals[3] = new JapaneseCalendar();
myCals[4] = new KoreanCalendar();
myCals[5] = new TaiwanCalendar();
myCals[6] = new ThaiBuddhistCalendar();
// For each calendar, displays the current year, the number of months in that year,
// and the number of days in each month of that year.
int i, j, iYear, iMonth, iDay;
DateTime myDT = DateTime.Today;
for (i = 0; i < myCals.Length; i++)
{
iYear = myCals[i].GetYear(myDT);
outputBlock.Text += "\n";
outputBlock.Text += String.Format("{0}, Year: {1}", myCals[i].GetType(), myCals[i].GetYear(myDT)) + "\n";
outputBlock.Text += String.Format(" MonthsInYear: {0}", myCals[i].GetMonthsInYear(iYear)) + "\n";
outputBlock.Text += String.Format(" DaysInYear: {0}", myCals[i].GetDaysInYear(iYear)) + "\n";
outputBlock.Text += " Days in each month:" + "\n";
outputBlock.Text += " ";
for (j = 1; j <= myCals[i].GetMonthsInYear(iYear); j++)
outputBlock.Text += String.Format(" {0,-5}", myCals[i].GetDaysInMonth(iYear, j));
outputBlock.Text += "\n";
iMonth = myCals[i].GetMonth(myDT);
iDay = myCals[i].GetDayOfMonth(myDT);
outputBlock.Text += String.Format(" IsLeapDay: {0}", myCals[i].IsLeapDay(iYear, iMonth, iDay)) + "\n";
outputBlock.Text += String.Format(" IsLeapMonth: {0}", myCals[i].IsLeapMonth(iYear, iMonth)) + "\n";
outputBlock.Text += String.Format(" IsLeapYear: {0}", myCals[i].IsLeapYear(iYear)) + "\n";
}
}
}
/*
This code produces the following output. The results vary depending on the date.
System.Globalization.GregorianCalendar, Year: 2002
MonthsInYear: 12
DaysInYear: 365
Days in each month:
31 28 31 30 31 30 31 31 30 31 30 31
IsLeapDay: False
IsLeapMonth: False
IsLeapYear: False
System.Globalization.HebrewCalendar, Year: 5763
MonthsInYear: 13
DaysInYear: 385
Days in each month:
30 30 30 29 30 30 29 30 29 30 29 30 29
IsLeapDay: False
IsLeapMonth: False
IsLeapYear: True
System.Globalization.HijriCalendar, Year: 1423
MonthsInYear: 12
DaysInYear: 355
Days in each month:
30 29 30 29 30 29 30 29 30 29 30 30
IsLeapDay: False
IsLeapMonth: False
IsLeapYear: True
System.Globalization.JapaneseCalendar, Year: 14
MonthsInYear: 12
DaysInYear: 365
Days in each month:
31 28 31 30 31 30 31 31 30 31 30 31
IsLeapDay: False
IsLeapMonth: False
IsLeapYear: False
System.Globalization.JulianCalendar, Year: 2002
MonthsInYear: 12
DaysInYear: 365
Days in each month:
31 28 31 30 31 30 31 31 30 31 30 31
IsLeapDay: False
IsLeapMonth: False
IsLeapYear: False
System.Globalization.KoreanCalendar, Year: 4335
MonthsInYear: 12
DaysInYear: 365
Days in each month:
31 28 31 30 31 30 31 31 30 31 30 31
IsLeapDay: False
IsLeapMonth: False
IsLeapYear: False
System.Globalization.TaiwanCalendar, Year: 91
MonthsInYear: 12
DaysInYear: 365
Days in each month:
31 28 31 30 31 30 31 31 30 31 30 31
IsLeapDay: False
IsLeapMonth: False
IsLeapYear: False
System.Globalization.ThaiBuddhistCalendar, Year: 2545
MonthsInYear: 12
DaysInYear: 365
Days in each month:
31 28 31 30 31 30 31 31 30 31 30 31
IsLeapDay: False
IsLeapMonth: False
IsLeapYear: 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.