Calendar.GetDaysInMonth Method

Definition

When overridden in a derived class, returns the number of days in the specified month.

Overloads

GetDaysInMonth(Int32, Int32)

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

GetDaysInMonth(Int32, Int32, Int32)

When overridden in a derived class, returns the number of days in the specified month, year, and era.

GetDaysInMonth(Int32, Int32)

Source:
Calendar.cs
Source:
Calendar.cs
Source:
Calendar.cs

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

C#
public virtual int GetDaysInMonth (int year, int month);

Parameters

year
Int32

An integer that represents the year.

month
Int32

A positive integer that represents the month.

Returns

The number of days in the specified month in the specified year in the current era.

Exceptions

year is outside the range supported by the calendar.

-or-

month is outside the range supported by the calendar.

Examples

The following code example compares different implementations of the Calendar class.

C#
using System;
using System.Globalization;

public class SamplesCalendar  {

   public static void Main()  {

      // Creates an instance of every Calendar type.
      Calendar[] myCals = new Calendar[8];
      myCals[0] = new GregorianCalendar();
      myCals[1] = new HebrewCalendar();
      myCals[2] = new HijriCalendar();
      myCals[3] = new JapaneseCalendar();
      myCals[4] = new JulianCalendar();
      myCals[5] = new KoreanCalendar();
      myCals[6] = new TaiwanCalendar();
      myCals[7] = 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 );
         Console.WriteLine();
         Console.WriteLine( "{0}, Year: {1}", myCals[i].GetType(), myCals[i].GetYear( myDT ) );
         Console.WriteLine( "   MonthsInYear: {0}", myCals[i].GetMonthsInYear( iYear ) );
         Console.WriteLine( "   DaysInYear: {0}", myCals[i].GetDaysInYear( iYear ) );
         Console.WriteLine( "   Days in each month:" );
         Console.Write( "      " );

         for ( j = 1; j <= myCals[i].GetMonthsInYear( iYear ); j++ )
            Console.Write( " {0,-5}", myCals[i].GetDaysInMonth( iYear, j ) );
         Console.WriteLine();

         iMonth = myCals[i].GetMonth( myDT );
         iDay = myCals[i].GetDayOfMonth( myDT );
         Console.WriteLine( "   IsLeapDay:   {0}", myCals[i].IsLeapDay( iYear, iMonth, iDay ) );
         Console.WriteLine( "   IsLeapMonth: {0}", myCals[i].IsLeapMonth( iYear, iMonth ) );
         Console.WriteLine( "   IsLeapYear:  {0}", myCals[i].IsLeapYear( iYear ) );
      }
   }
}


/*
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

*/

Remarks

For example, in GregorianCalendar, GetDaysInMonth for February returns 28 in a common year or 29 in a leap year.

See also

Applies to

.NET 9 and other versions
Product Versions
.NET Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9
.NET Framework 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
.NET Standard 1.0, 1.1, 1.2, 1.3, 1.4, 1.6, 2.0, 2.1
UWP 10.0

GetDaysInMonth(Int32, Int32, Int32)

Source:
Calendar.cs
Source:
Calendar.cs
Source:
Calendar.cs

When overridden in a derived class, returns the number of days in the specified month, year, and era.

C#
public abstract int GetDaysInMonth (int year, int month, int era);

Parameters

year
Int32

An integer that represents the year.

month
Int32

A positive integer that represents the month.

era
Int32

An integer that represents the era.

Returns

The number of days in the specified month in the specified year in the specified era.

Exceptions

year is outside the range supported by the calendar.

-or-

month is outside the range supported by the calendar.

-or-

era is outside the range supported by the calendar.

Remarks

For example, in GregorianCalendar, GetDaysInMonth for February returns 28 in a common year or 29 in a leap year.

Notes to Implementers

The derived class must support CurrentEra when it is passed as the era parameter. One way to support CurrentEra is by replacing it with the value stored in Eras[0], which is the value for the current era of the calendar.

See also

Applies to

.NET 9 and other versions
Product Versions
.NET Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9
.NET Framework 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
.NET Standard 1.0, 1.1, 1.2, 1.3, 1.4, 1.6, 2.0, 2.1
UWP 10.0