• Article

DateTime.DaysInMonth Method

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

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

Syntax

'Declaration
Public Shared Function DaysInMonth ( _
    year As Integer, _
    month As Integer _
) As Integer

public static int DaysInMonth(
    int year,
    int month
)

Parameters

  • month
    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 on whether year is a leap year.

Exceptions

Exception Condition
ArgumentOutOfRangeException

month is less than 1 or greater than 12.

-or-

year is less than 1 or greater than 9999.

Examples

The following example demonstrates the DaysInMonth method.

Const July As Integer = 7
Const Feb As Integer = 2

' daysInJuly gets 31.
Dim daysInJuly As Integer = System.DateTime.DaysInMonth(2001, July)

' daysInFeb gets 28 because the year 1998 was not a leap year.
Dim daysInFeb As Integer = System.DateTime.DaysInMonth(1998, Feb)

' daysInFebLeap gets 29 because the year 1996 was a leap year.
Dim daysInFebLeap As Integer = System.DateTime.DaysInMonth(1996, Feb)

const int July = 7;
const int Feb = 2;

// daysInJuly gets 31.
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);

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.