DateTime.DayOfYear DateTime.DayOfYear DateTime.DayOfYear DateTime.DayOfYear Property

定義

このインスタンスで表される年間積算日を取得します。Gets the day of the year represented by this instance.

public:
 property int DayOfYear { int get(); };
public int DayOfYear { get; }
member this.DayOfYear : int
Public ReadOnly Property DayOfYear As Integer

プロパティ値

1 から 366 までの間の積算日。The day of the year, expressed as a value between 1 and 366.

次の例では、グレゴリオ暦の2010-2020 年の年12月31日を表示します。The following example displays the day of the year of December 31 for the years 2010-2020 in the Gregorian calendar. この例では、12月31日がうるう年の年の36番目の日であることが示されています。Note that the example shows that December 31 is the 366th day of the year in leap years.

using System;

public class Example
{
   public static void Main()
   {
      DateTime dec31 = new DateTime(2010, 12, 31);
      for (int ctr = 0; ctr <= 10; ctr++) {
         DateTime dateToDisplay = dec31.AddYears(ctr);
         Console.WriteLine("{0:d}: day {1} of {2} {3}", dateToDisplay, 
                           dateToDisplay.DayOfYear,
                           dateToDisplay.Year,   
                           DateTime.IsLeapYear(dateToDisplay.Year) ? 
                                               "(Leap Year)" : ""); 
      }  

   }
}
// The example displays the following output:
//       12/31/2010: day 365 of 2010
//       12/31/2011: day 365 of 2011
//       12/31/2012: day 366 of 2012 (Leap Year)
//       12/31/2013: day 365 of 2013
//       12/31/2014: day 365 of 2014
//       12/31/2015: day 365 of 2015
//       12/31/2016: day 366 of 2016 (Leap Year)
//       12/31/2017: day 365 of 2017
//       12/31/2018: day 365 of 2018
//       12/31/2019: day 365 of 2019
//       12/31/2020: day 366 of 2020 (Leap Year)
Option Strict On

Module Example
   Public Sub Main()
      Dim dec31 As Date = #12/31/2010#
      For ctr As Integer = 0 To 10
         Dim dateToDisplay As Date = dec31.AddYears(ctr)
         Console.WriteLine("{0:d}: day {1} of {2} {3}", dateToDisplay, 
                           dateToDisplay.DayOfYear,
                           dateToDisplay.Year,   
                           If(DateTime.IsLeapYear(dateToDisplay.Year), 
                                                  "(Leap Year)", "")) 
                           
      Next
   End Sub
End Module
' The example displays the following output:
'       12/31/2010: day 365 of 2010
'       12/31/2011: day 365 of 2011
'       12/31/2012: day 366 of 2012 (Leap Year)
'       12/31/2013: day 365 of 2013
'       12/31/2014: day 365 of 2014
'       12/31/2015: day 365 of 2015
'       12/31/2016: day 366 of 2016 (Leap Year)
'       12/31/2017: day 365 of 2017
'       12/31/2018: day 365 of 2018
'       12/31/2019: day 365 of 2019
'       12/31/2020: day 366 of 2020 (Leap Year)

注釈

プロパティDayOfYearは、年の日付を計算するときに、うるう年を考慮します。The DayOfYear property takes leap years into account when it calculates the day of the year. プロパティ値は、現在のスレッドカルチャの現在の暦に関係なく、グレゴリオ暦の年の日付を常に反映します。The property value always reflects the day of the year in the Gregorian calendar, regardless of the current thread culture's current calendar. 別の暦で年の日付を取得するには、そのCalendar.GetDayOfYear暦のメソッドを呼び出します。To retrieve the day of the year in a different calendar, call the Calendar.GetDayOfYear method of that calendar.

適用対象

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