Calendar.GetWeekOfYear(DateTime, CalendarWeekRule, DayOfWeek) 方法

定義

命名空間:

System.Globalization

組件:

System.Runtime.dll

來源:

Calendar.cs

傳回年份中的週，其中包含指定之 DateTime 值中的日期。

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

public virtual int GetWeekOfYear (DateTime time, System.Globalization.CalendarWeekRule rule, DayOfWeek firstDayOfWeek);

abstract member GetWeekOfYear : DateTime * System.Globalization.CalendarWeekRule * DayOfWeek -> int
override this.GetWeekOfYear : DateTime * System.Globalization.CalendarWeekRule * DayOfWeek -> int

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

參數

time

DateTime

日期和時間值。

rule

CalendarWeekRule

定義日曆週的列舉值。

firstDayOfWeek

DayOfWeek

代表一週第一天的列舉值。

傳回

Int32

正整數，表示 time 參數中日期所屬年份中的某週。

例外狀況

ArgumentOutOfRangeException

time 早於 MinSupportedDateTime 或晚於 MaxSupportedDateTime。

-或-

firstDayOfWeek 不是有效的 DayOfWeek 值。

-或-

rule 不是有效的 CalendarWeekRule 值。

範例

下列程式碼範例顯示 的結果 GetWeekOfYear 如何根據 FirstDayOfWeek 和 CalendarWeekRule 所使用的 而有所不同。 如果指定的日期是年份的最後一天， GetWeekOfYear 則傳回該年份中的周總數。

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).
*/

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).

*/

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
End Class


'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).

備註

這個方法可用來藉由將 設定 time 為年份的最後一天來判斷年份中的周數。

DateTimeFormatInfo使用 屬性所指示 DateTimeFormatInfo.Calendar 之行事曆的特定文化特性物件包含下列可用於 rule 和 firstDayOfWeek 參數的文化特性特定值：

• 屬性 DateTimeFormatInfo.FirstDayOfWeek 包含一周的預設第一天，可用於 firstDayOfWeek 參數。

• 屬性 DateTimeFormatInfo.CalendarWeekRule 包含可用於 參數的預設行事曆周規則 rule 。

注意

這不會完全對應至 ISO 8601。 部落格文章ISO 8601 Year 格式Microsoft .NET會討論差異。 從 .NET Core 3.0 開始， ISOWeek.GetYear 並 ISOWeek.GetWeekOfYear 解決此問題。

下列範例會使用目前文化特性的物件 DateTimeFormatInfo 來判斷 2011 年 1 月 1 日是在西曆的第一周。

using System;
using System.Globalization;

public class Example
{
   public static void Main()
   {
      DateTimeFormatInfo dfi = DateTimeFormatInfo.CurrentInfo;
      DateTime date1 = new DateTime(2011, 1, 1);
      Calendar cal = dfi.Calendar;

      Console.WriteLine("{0:d}: Week {1} ({2})", date1,
                        cal.GetWeekOfYear(date1, dfi.CalendarWeekRule,
                                          dfi.FirstDayOfWeek),
                        cal.ToString().Substring(cal.ToString().LastIndexOf(".") + 1));
   }
}
// The example displays the following output:
//       1/1/2011: Week 1 (GregorianCalendar)

Imports System.Globalization

Module Example
   Public Sub Main()
      Dim dfi As DateTimeFormatInfo = DateTimeFormatInfo.CurrentInfo
      Dim date1 As Date = #1/1/2011#
      Dim cal As Calendar = dfi.Calendar
      
      Console.WriteLine("{0:d}: Week {1} ({2})", date1, 
                        cal.GetWeekOfYear(date1, dfi.CalendarWeekRule, 
                                          dfi.FirstDayOfWeek),
                        cal.ToString().Substring(cal.ToString().LastIndexOf(".") + 1))       
   End Sub
End Module
' The example displays the following output:
'       1/1/2011: Week 1 (GregorianCalendar)

對於某些行事曆，即使大於該行事曆 MinSupportedDateTime 屬性所傳回的日期，方法的呼叫 GetWeekOfYear 也會 ArgumentOutOfRangeException 針對 和 firstDayOfWeek 值 time 的特定組合 rule 擲回 。 下表列出受影響的行事曆、特定 rule 值，以及最早支援 time 值的範圍。 特定的最小值 DateTime 取決於 參數的值 firstDayOfWeek 。

Calendar	CalendarWeekRule 值	西曆日期 (M/dd/yyyy)	行事曆中的日期 (M/dd/yyyy)
ChineseLunisolarCalendar	FirstFullWeek	2/19/1901 到 2/25/1901	1/1/1901 到 1/7/1901
ChineseLunisolarCalendar	FirstFourDayWeek	2/19/1901 到 2/22/1901	1/01/1901 到 1/04/1901
HebrewCalendar	FirstDay	9/17/1583	1/01/5344
HebrewCalendar	FirstFullWeek	9/17/1583 至 9/23/1583	1/01/5344 至 1/07/5344
HebrewCalendar	FirstFourDayWeek	9/17/1583 到 9/20/1583	1/01/5344 至 1/04/5344
HijriCalendar	FirstFullWeek	7/18/0622 至 7/24/0622	1/01/0001 至 1/07/0001
HijriCalendar	FirstFourDayWeek	7/18/0622 至 7/21/0622	1/01/0001 至 1/04/0001
JapaneseLunisolarCalendar	FirstFullWeek	1/28/1960 到 2/03/1960	1/01/35 至 1/07/0035
JapaneseLunisolarCalendar	FirstFourDayWeek	1/28/1960 到 1/31/1960	1/0035 至 1/04/0035
JulianCalendar	FirstFullWeek	1/01/0001 至 1/05/0001	1/03/0001 至 1/07/0001
JulianCalendar	FirstFourDayWeek	1/01/0001 至 1/02/0001	1/03/0001 至 1/04/0001
KoreanLunisolarCalendar	FirstFullWeek	2/14/0918 至 2/20/0918	1/01/0918 至 1/07/0918
KoreanLunisolarCalendar	FirstFourDayWeek	2/14/0918 至 2/17/0918	1/01/0918 至 1/04/0918
PersianCalendar	FirstFullWeek	3/21/0622 至 3/27/0622	1/01/0001 至 1/07/0001
PersianCalendar	FirstFourDayWeek	3/21/0622 至 3/24/0622	1/01/0001 至 1/04/0001
TaiwanLunisolarCalendar	FirstFullWeek	2/18/1912 至 2/24/1912	1/01/0001 至 1/07/0001
TaiwanLunisolarCalendar	FirstFourDayWeek	2/18/1912 至 2/21/1912	1/01/0001 至 1/04/0001
UmAlQuraCalendar	FirstFullWeek	4/30/1900 到 5/06/1900	1/01/1318 到 1/07/1318
UmAlQuraCalendar	FirstFourDayWeek	4/30/1900 到 5/03/1900	1/01/1318 至 1/04/1318

另請參閱

• DateTime
• CalendarWeekRule
• DayOfWeek
• GetEra(DateTime)
• GetYear(DateTime)
• GetMonth(DateTime)
• GetDayOfYear(DateTime)
• GetDayOfMonth(DateTime)
• GetDayOfWeek(DateTime)
• GetHour(DateTime)
• GetMinute(DateTime)
• GetSecond(DateTime)
• GetMilliseconds(DateTime)