DateTime.IsLeapYear Method
[ This article is for Windows Phone 8 developers. If you’re developing for Windows 10, see the latest documentation. ]
Returns an indication whether the specified year is a leap year.
Namespace: System
Assembly: mscorlib (in mscorlib.dll)
Syntax
Public Shared Function IsLeapYear ( _
year As Integer _
) As Boolean
public static bool IsLeapYear(
int year
)
Parameters
- year
Type: System..::.Int32
A 4-digit year.
Return Value
Type: System..::.Boolean
true if year is a leap year; otherwise, false.
Exceptions
| Exception | Condition |
|---|---|
| ArgumentOutOfRangeException | year is less than 1 or greater than 9999. |
Remarks
year is specified as a 4-digit base 10 number; for example, 1996.
year is always interpreted as a year in the Gregorian calendar. To determine whether a particular year was a leap year in some other calendar, call that calendar object's IsLeapYear method.
Examples
The following example uses the IsLeapYear method to determine which years between 1994 and 2014 are leap years. The example also illustrates the result when the AddYears method is used to add a year to a leap day.
Module Example
Public Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)
For year As Integer = 1994 To 2014
If DateTime.IsLeapYear(year) Then
outputBlock.Text += String.Format("{0} is a leap year.", year) & vbCrLf
Dim leapDay As New Date(year, 2, 29)
Dim nextYear As Date = leapDay.AddYears(1)
outputBlock.Text += String.Format(" One year from {0} is {1}.", _
leapDay.ToString("d"), _
nextYear.ToString("d")) & vbCrLf
End If
Next
End Sub
End Module
' The example displays the following output:
' 1996 is a leap year.
' One year from 2/29/1996 is 2/28/1997.
' 2000 is a leap year.
' One year from 2/29/2000 is 2/28/2001.
' 2004 is a leap year.
' One year from 2/29/2004 is 2/28/2005.
' 2008 is a leap year.
' One year from 2/29/2008 is 2/28/2009.
' 2012 is a leap year.
' One year from 2/29/2012 is 2/28/2013.
using System;
public class Example
{
public static void Demo(System.Windows.Controls.TextBlock outputBlock)
{
for (int year = 1994; year <= 2014; year++)
{
if (DateTime.IsLeapYear(year))
{
outputBlock.Text += String.Format("{0} is a leap year.", year) + "\n";
DateTime leapDay = new DateTime(year, 2, 29);
DateTime nextYear = leapDay.AddYears(1);
outputBlock.Text += String.Format(" One year from {0} is {1}.",
leapDay.ToString("d"),
nextYear.ToString("d")) + "\n";
}
}
}
}
// The example produces the following output:
// 1996 is a leap year.
// One year from 2/29/1996 is 2/28/1997.
// 2000 is a leap year.
// One year from 2/29/2000 is 2/28/2001.
// 2004 is a leap year.
// One year from 2/29/2004 is 2/28/2005.
// 2008 is a leap year.
// One year from 2/29/2008 is 2/28/2009.
// 2012 is a leap year.
// One year from 2/29/2012 is 2/28/2013.
Version Information
Windows Phone OS
Supported in: 8.1, 8.0, 7.1, 7.0
Platforms
Windows Phone