Calendar.GetWeekOfYear メソッド

.NET Framework クラス ライブラリ リファレンス

Calendar.GetWeekOfYear メソッド

指定した DateTime の日付を含むその年の週を返します。

名前空間: System.Globalization
アセンブリ: mscorlib (mscorlib.dll 内)
構文

Visual Basic (宣言)

Public Overridable Function
 GetWeekOfYear ( _
    time As DateTime, _
    rule As CalendarWeekRule, _
    firstDayOfWeek As DayOfWeek _
) As Integer

Visual Basic (使用法)

Dim instance As Calendar
Dim time As DateTime
Dim rule As CalendarWeekRule
Dim firstDayOfWeek As DayOfWeek
Dim returnValue As Integer

returnValue = instance.GetWeekOfYear(time, rule, firstDayOfWeek)

C#

public virtual int GetWeekOfYear (
    DateTime time,
    CalendarWeekRule rule,
    DayOfWeek firstDayOfWeek
)

C++

public:
virtual int GetWeekOfYear (
    DateTime time, 
    CalendarWeekRule rule, 
    DayOfWeek firstDayOfWeek
)

J#

public int GetWeekOfYear (
    DateTime time, 
    CalendarWeekRule rule, 
    DayOfWeek firstDayOfWeek
)

JScript

public function GetWeekOfYear (
    time : DateTime, 
    rule : CalendarWeekRule, 
    firstDayOfWeek : DayOfWeek
) : int

パラメータ

time

読み取る対象の DateTime。

rule

暦の週を定義する CalendarWeekRule 値。

firstDayOfWeek

週の最初の日を表す DayOfWeek 値。

戻り値
time パラメータの日付を含む年の週を表す正の整数。

例外

例外の種類	条件
ArgumentOutOfRangeException	firstDayOfWeek が暦でサポートされている範囲外の値です。 または rule が有効な CalendarWeekRule 値ではありません。

解説

このメソッドは、その年の最後の日付を time に設定することにより、その年の週の数を確認するために使用できます。

CultureInfo.DateTimeFormat プロパティには、rule と firstDayOfWeek に使用できるカルチャ固有の値が含まれます。

CultureInfo.DateTimeFormat の FirstDayOfWeek プロパティには、CultureInfo.DateTimeFormat の Calendar プロパティで指定された暦を使用して、特定のカルチャにおける週の最初の曜日を表す既定の DayOfWeek 値が格納されます。

CultureInfo.DateTimeFormat の CalendarWeekRule プロパティには、CultureInfo.DateTimeFormat の Calendar プロパティを使用して、特定のカルチャの暦における週を定義する既定の CalendarWeekRule 値が格納されます。

たとえば、GregorianCalendar では、GetWeekOfYear メソッドは、1 月 1 日に対して 1 を返します。

使用例

使用する FirstDayOfWeek と CalendarWeekRule に応じて GetWeekOfYear の結果が変わるようすを示すコードの例を次に示します。指定した日付がその年の最後の日だった場合、GetWeekOfYear はその年の週の総数を返します。

Visual Basic

Imports System
Imports System.Globalization

Public Class SamplesCalendar

   Public Shared Sub Main()
      
      ' Gets the Calendar instance associated with a CultureInfo.
      Dim myCI As New CultureInfo("en-US")
      Dim myCal As Calendar = myCI.Calendar
      
      ' Gets the DTFI properties required by GetWeekOfYear.
      Dim myCWR As CalendarWeekRule = myCI.DateTimeFormat.CalendarWeekRule
      Dim myFirstDOW As DayOfWeek = myCI.DateTimeFormat.FirstDayOfWeek
      
      ' Displays the number of the current week relative to the beginning
 of the year.
      Console.WriteLine("The CalendarWeekRule used for the en-US
 culture is {0}.", myCWR)
      Console.WriteLine("The FirstDayOfWeek used for the en-US
 culture is {0}.", myFirstDOW)
      Console.WriteLine("Therefore, the current week is Week {0}
 of the current year.", myCal.GetWeekOfYear(DateTime.Now, myCWR, myFirstDOW))
      
      ' Displays the total number of weeks in the current year.
      Dim LastDay = New System.DateTime(DateTime.Now.Year,
 12, 31)
      Console.WriteLine("There are {0} weeks in the current year
 ({1}).", myCal.GetWeekOfYear(LastDay, myCWR, myFirstDOW), LastDay.Year)
   End Sub 'Main 
End Class 'SamplesCalendar


'This code produces the following output.  Results vary depending on
 the system date.
'
'The CalendarWeekRule used for the en-US culture is FirstDay.
'The FirstDayOfWeek used for the en-US culture is Sunday.
'Therefore, the current week is Week 1 of the current year.
'There are 53 weeks in the current year (2001).

C#

using System;
using System.Globalization;


public class SamplesCalendar  {

   public static void Main()
  {

      // Gets the Calendar instance associated with a CultureInfo.
      CultureInfo myCI = new CultureInfo("en-US");
      Calendar myCal = myCI.Calendar;

      // Gets the DTFI properties required by GetWeekOfYear.
      CalendarWeekRule myCWR = myCI.DateTimeFormat.CalendarWeekRule;
      DayOfWeek myFirstDOW = myCI.DateTimeFormat.FirstDayOfWeek;

      // Displays the number of the current week relative to the beginning
 of the year.
      Console.WriteLine( "The CalendarWeekRule used for the
 en-US culture is {0}.", myCWR );
      Console.WriteLine( "The FirstDayOfWeek used for the
 en-US culture is {0}.", myFirstDOW );
      Console.WriteLine( "Therefore, the current week is Week {0} of the current
 year.", myCal.GetWeekOfYear( DateTime.Now, myCWR, myFirstDOW ));

      // Displays the total number of weeks in the current year.
      DateTime LastDay = new System.DateTime( DateTime.Now.Year,
 12, 31 );
      Console.WriteLine( "There are {0} weeks in the current
 year ({1}).", myCal.GetWeekOfYear( LastDay, myCWR, myFirstDOW ), LastDay.Year
 );

   }

}

/*
This code produces the following output.  Results vary depending on the system date.

The CalendarWeekRule used for the en-US culture is FirstDay.
The FirstDayOfWeek used for the en-US culture is Sunday.
Therefore, the current week is Week 1 of the current year.
There are 53 weeks in the current year (2001).

*/

C++

using namespace System;
using namespace System::Globalization;
int main()
{
   
   // Gets the Calendar instance associated with a CultureInfo.
   CultureInfo^ myCI = gcnew CultureInfo( "en-US" );
   Calendar^ myCal = myCI->Calendar;
   
   // Gets the DTFI properties required by GetWeekOfYear.
   CalendarWeekRule myCWR = myCI->DateTimeFormat->CalendarWeekRule;
   DayOfWeek myFirstDOW = myCI->DateTimeFormat->FirstDayOfWeek;
   
   // Displays the number of the current week relative to the beginning
 of the year.
   Console::WriteLine( "The CalendarWeekRule used for the
 en-US culture is {0}.", myCWR );
   Console::WriteLine( "The FirstDayOfWeek used for the en-US
 culture is {0}.", myFirstDOW );
   Console::WriteLine( "Therefore, the current week is Week {0} of the current
 year.", myCal->GetWeekOfYear( DateTime::Now, myCWR, myFirstDOW ) );
   
   // Displays the total number of weeks in the current year.
   DateTime LastDay = System::DateTime( DateTime::Now.Year, 12, 31 );
   Console::WriteLine( "There are {0} weeks in the current
 year ( {1}).", myCal->GetWeekOfYear( LastDay, myCWR, myFirstDOW ), LastDay.Year
 );
}

/*
This code produces the following output.  Results vary depending on the system date.

The CalendarWeekRule used for the en-US culture is FirstDay.
The FirstDayOfWeek used for the en-US culture is Sunday.
Therefore, the current week is Week 1 of the current year.
There are 53 weeks in the current year (2001).
*/

J#

import System.* ;
import System.Globalization.* ;

public class SamplesCalendar
{
    public static void main(String[]
 args)
    {
        // Gets the Calendar instance associated with a CultureInfo.
        CultureInfo myCI =  new CultureInfo("en-US");
        Calendar myCal = myCI.get_Calendar();

        // Gets the DTFI properties required by GetWeekOfYear.
        CalendarWeekRule myCWR = 
            myCI.get_DateTimeFormat().get_CalendarWeekRule();
        DayOfWeek myFirstDOW = myCI.get_DateTimeFormat().get_FirstDayOfWeek();

        // Displays the number of the current week relative to the 
        // beginning of the year.
        Console.WriteLine("The CalendarWeekRule used for
 the en-US culture " 
            + "is {0}.", myCWR);
        Console.WriteLine("The FirstDayOfWeek used for the
 en-US culture " 
            + "is {0}.", myFirstDOW);
        Console.WriteLine("Therefore, the current week is Week {0} of the "
 
            + "current year.", System.Convert.ToString( myCal.GetWeekOfYear(
            DateTime.get_Now(),myCWR, myFirstDOW)));

        // Displays the total number of weeks in the current year.
        DateTime LastDay = 
            new System.DateTime(DateTime.get_Now().get_Year(),
 12, 31);
        Console.WriteLine("There are {0} weeks in the current
 year ({1}).",
            System.Convert.ToString(myCal.GetWeekOfYear(LastDay, myCWR, 
            myFirstDOW)),System.Convert.ToString( LastDay.get_Year()));
    } //main 
} //SamplesCalendar

/*
This code produces the following output.  Results vary depending on the 
system date.

The CalendarWeekRule used for the en-US culture is FirstDay.
The FirstDayOfWeek used for the en-US culture is Sunday.
Therefore, the current week is Week 15 of the current year.
There are 53 weeks in the current year (2004).
*/

プラットフォーム

Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

開発プラットフォームの中には、.NET Framework によってサポートされていないバージョンがあります。サポートされているバージョンについては、「システム要件」を参照してください。

バージョン情報

.NET Framework
サポート対象 : 2.0、1.1、1.0
.NET Compact Framework
サポート対象 : 2.0、1.0

参照

関連項目
Calendar クラス
Calendar メンバ
System.Globalization 名前空間
System.DateTime
CalendarWeekRule
System.DayOfWeek
GetEra
GetYear
GetMonth
GetDayOfYear
GetDayOfMonth
GetDayOfWeek
GetHour
GetMinute
GetSecond
GetMilliseconds