DateTime::DaysInMonth Method (Int32, Int32)


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Returns the number of days in the specified month and year.

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

static int DaysInMonth(
	int year,
	int month


Type: System::Int32

The year.

Type: System::Int32

The month (a number ranging from 1 to 12).

Return Value

Type: System::Int32

The number of days in month for the specified year.

For example, if month equals 2 for February, the return value is 28 or 29 depending upon whether year is a leap year.

Exception Condition

month is less than 1 or greater than 12.


year is less than 1 or greater than 9999.

TheDaysInMonth method always interprets month and year as the month and year of the Gregorian calendar even if the Gregorian calendar is not the current culture's current calendar. To get the number of days in a specified month of a particular calendar, call that calendar's GetDaysInMonth method.

The following example demonstrates how to use the DaysInMonth method to determine the number of days in July 2001, February 1998 (a non-leap year), and February 1996 (a leap year).

using namespace System;

int main()
   const int July = 7;
   const int Feb = 2;

   int daysInJuly = System::DateTime::DaysInMonth( 2001, July );
   // daysInFeb gets 28 because the year 1998 was not a leap year.
   int daysInFeb = System::DateTime::DaysInMonth( 1998, Feb );
   // daysInFebLeap gets 29 because the year 1996 was a leap year.
   int daysInFebLeap = System::DateTime::DaysInMonth( 1996, Feb );
// The example displays the following output:
//       31
//       28
//       29

The following example displays the number of days in each month of a year specified in an integer array.

No code example is currently available or this language may not be supported.

Universal Windows Platform
Available since 8
.NET Framework
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
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