TimeZoneInfo.AdjustmentRule.DateEnd Proprietà

  • Riferimento

Definizione

Spazio dei nomi:
System
Assembly:
System.Runtime.dll
Assembly:
System.Core.dll
Assembly:
mscorlib.dll
Assembly:
netstandard.dll
Origine:
TimeZoneInfo.AdjustmentRule.cs
Origine:
TimeZoneInfo.AdjustmentRule.cs
Origine:
TimeZoneInfo.AdjustmentRule.cs

Ottiene la data in cui la regola di rettifica cessa di essere effettiva.

public:
 property DateTime DateEnd { DateTime get(); };
public DateTime DateEnd { get; }
member this.DateEnd : DateTime
Public ReadOnly Property DateEnd As DateTime

Valore della proprietà

DateTime

Valore di DateTime che indica la data di scadenza della regola di rettifica.

Esempio

Nell'esempio seguente vengono visualizzate informazioni su tutti i fusi orari definiti nel Registro di sistema del computer locale, incluse le date di inizio e fine delle regole di rettifica.

using System;
using System.Collections.ObjectModel;
using System.Globalization;

public class Example
{
   public static void Main()
   {
      ReadOnlyCollection<TimeZoneInfo> timeZones = TimeZoneInfo.GetSystemTimeZones();
      DateTimeFormatInfo dateInfo = CultureInfo.CurrentCulture.DateTimeFormat;
      
      foreach (var zone in timeZones)
      {
         Console.WriteLine("{0} transition time information:", zone.StandardName);
         Console.WriteLine("   Time zone information: ");
         Console.WriteLine("      Base UTC Offset: {0}", zone.BaseUtcOffset);
         Console.WriteLine("      Supports DST: {0}", zone.SupportsDaylightSavingTime);

         TimeZoneInfo.AdjustmentRule[] adjustmentRules= zone.GetAdjustmentRules();
         
         // Indicate that time zone has no adjustment rules
         if (adjustmentRules.Length == 0) {
            Console.WriteLine("      No adjustment rules defined.");
         }   
         else {
            Console.WriteLine("      Adjustment Rules: {0}", adjustmentRules.Length);
            // Iterate adjustment rules       
            foreach (var adjustmentRule in adjustmentRules) {
               Console.WriteLine("   Adjustment rule from {0:d} to {1:d}:", 
                                 adjustmentRule.DateStart, 
                                 adjustmentRule.DateEnd);                                 
               Console.WriteLine("      Delta: {0}", adjustmentRule.DaylightDelta);
               // Get start of transition
               TimeZoneInfo.TransitionTime daylightStart = adjustmentRule.DaylightTransitionStart;
               // Display information on floating date rule
               if (! daylightStart.IsFixedDateRule)
                  Console.WriteLine("      Begins at {0:t} on the {1} {2} of {3}", 
                                 daylightStart.TimeOfDay, 
                                 (WeekOfMonth) daylightStart.Week,  
                                 daylightStart.DayOfWeek, 
                                 dateInfo.GetMonthName(daylightStart.Month));
               // Display information on fixed date rule 
               else
                  Console.WriteLine("      Begins at {0:t} on {1} {2}", 
                                    daylightStart.TimeOfDay, 
                                    dateInfo.GetMonthName(daylightStart.Month), 
                                    daylightStart.Day);
               
               // Get end of transition.
              TimeZoneInfo.TransitionTime daylightEnd = adjustmentRule.DaylightTransitionEnd;
               // Display information on floating date rule.
               if (!daylightEnd.IsFixedDateRule) 
                  Console.WriteLine("      Ends at {0:t} on the {1} {2} of {3}", 
                                 daylightEnd.TimeOfDay, 
                                 (WeekOfMonth) daylightEnd.Week,  
                                 daylightEnd.DayOfWeek, 
                                 dateInfo.GetMonthName(daylightEnd.Month));
               // Display information on fixed date rule.
               else
                  Console.WriteLine("      Ends at {0:t} on {1} {2}", 
                                    daylightEnd.TimeOfDay, 
                                    dateInfo.GetMonthName(daylightEnd.Month), 
                                    daylightEnd.Day);
            }
         }   
      }   
   }

   private enum WeekOfMonth 
   {
      First = 1,
      Second = 2,
      Third = 3,
      Fourth = 4,
      Last = 5,
   }
}
// A portion of the output from the example might appear as follows:
//       Tonga Standard Time transition time information:
//          Time zone information:
//             Base UTC Offset: 13:00:00
//             Supports DST: False
//             No adjustment rules defined.
//       Samoa Standard Time transition time information:
//          Time zone information:
//             Base UTC Offset: 13:00:00
//             Supports DST: True
//             Adjustment Rules: 4
//          Adjustment rule from 1/1/0001 to 12/31/2009:
//             Delta: 00:00:00
//             Begins at 12:00 AM on January 1
//             Ends at 12:00 AM on January 1
//          Adjustment rule from 1/1/2010 to 12/31/2010:
//             Delta: 01:00:00
//             Begins at 11:59 PM on the Last Saturday of September
//             Ends at 12:00 AM on the First Friday of January
//          Adjustment rule from 1/1/2011 to 12/31/2011:
//             Delta: 01:00:00
//             Begins at 3:00 AM on the Fourth Saturday of September
//             Ends at 4:00 AM on the First Saturday of April
//          Adjustment rule from 1/1/2012 to 12/31/9999:
//             Delta: 01:00:00
//             Begins at 12:00 AM on the Last Sunday of September
//             Ends at 1:00 AM on the First Sunday of April
//       Line Islands Standard Time transition time information:
//          Time zone information:
//             Base UTC Offset: 14:00:00
//             Supports DST: False
//             No adjustment rules defined.

open System
open System.Globalization

let timeZones = TimeZoneInfo.GetSystemTimeZones()
let dateInfo = CultureInfo.CurrentCulture.DateTimeFormat

type WeekOfMonth = 
    | First = 1
    | Second = 2
    | Third = 3
    | Fourth = 4
    | Last = 5

for zone in timeZones do
    printfn $"{zone.StandardName} transition time information:"
    printfn "   Time zone information: "
    printfn $"      Base UTC Offset: {zone.BaseUtcOffset}"
    printfn $"      Supports DST: {zone.SupportsDaylightSavingTime}"

    let adjustmentRules= zone.GetAdjustmentRules()
    
    // Indicate that time zone has no adjustment rules
    if adjustmentRules.Length = 0 then
        printfn "      No adjustment rules defined."
    else
        printfn $"      Adjustment Rules: {adjustmentRules.Length}"
    // Iterate adjustment rules       
    for adjustmentRule in adjustmentRules do
        printfn $"   Adjustment rule from {adjustmentRule.DateStart:d} to {adjustmentRule.DateEnd:d}:"
        printfn $"      Delta: {adjustmentRule.DaylightDelta}"
        // Get start of transition
        let daylightStart = adjustmentRule.DaylightTransitionStart
        // Display information on floating date rule
        if not daylightStart.IsFixedDateRule then
            printfn $"      Begins at {daylightStart.TimeOfDay:t} on the {enum<WeekOfMonth> daylightStart.Week} {daylightStart.DayOfWeek} of {dateInfo.GetMonthName daylightStart.Month}"
        // Display information on fixed date rule 
        else
            printfn $"      Begins at {daylightStart.TimeOfDay:t} on {dateInfo.GetMonthName daylightStart.Month} {daylightStart.Day}"
        
        // Get end of transition.
        let daylightEnd = adjustmentRule.DaylightTransitionEnd
        // Display information on floating date rule.
        if not daylightEnd.IsFixedDateRule then
            printfn $"      Ends at {daylightEnd.TimeOfDay:t} on the {enum<WeekOfMonth> daylightEnd.Week} {daylightEnd.DayOfWeek} of {dateInfo.GetMonthName daylightEnd.Month}"
                            
        // Display information on fixed date rule.
        else
            printfn $"      Ends at {daylightEnd.TimeOfDay:t} on {dateInfo.GetMonthName daylightEnd.Month} {daylightEnd.Day}"

// A portion of the output from the example might appear as follows:
//       Tonga Standard Time transition time information:
//          Time zone information:
//             Base UTC Offset: 13:00:00
//             Supports DST: False
//             No adjustment rules defined.
//       Samoa Standard Time transition time information:
//          Time zone information:
//             Base UTC Offset: 13:00:00
//             Supports DST: True
//             Adjustment Rules: 4
//          Adjustment rule from 1/1/0001 to 12/31/2009:
//             Delta: 00:00:00
//             Begins at 12:00 AM on January 1
//             Ends at 12:00 AM on January 1
//          Adjustment rule from 1/1/2010 to 12/31/2010:
//             Delta: 01:00:00
//             Begins at 11:59 PM on the Last Saturday of September
//             Ends at 12:00 AM on the First Friday of January
//          Adjustment rule from 1/1/2011 to 12/31/2011:
//             Delta: 01:00:00
//             Begins at 3:00 AM on the Fourth Saturday of September
//             Ends at 4:00 AM on the First Saturday of April
//          Adjustment rule from 1/1/2012 to 12/31/9999:
//             Delta: 01:00:00
//             Begins at 12:00 AM on the Last Sunday of September
//             Ends at 1:00 AM on the First Sunday of April
//       Line Islands Standard Time transition time information:
//          Time zone information:
//             Base UTC Offset: 14:00:00
//             Supports DST: False
//             No adjustment rules defined.

Imports System.Collections.ObjectModel
Imports System.Globalization

Module Example
   Public Sub Main()
      Dim timeZones As ReadOnlyCollection(Of TimeZoneInfo) = TimeZoneInfo.GetSystemTimeZones()
      Dim dateInfo As DateTimeFormatInfo = CultureInfo.CurrentCulture.DateTimeFormat
      
      For Each zone In timeZones
         Console.WriteLine("{0} transition time information:", zone.StandardName)
         Console.WriteLine("   Time zone information: ")
         Console.WriteLine("      Base UTC Offset: {0}", zone.BaseUtcOffset)
         Console.WriteLine("      Supports DST: {0}", zone.SupportsDaylightSavingTime)

         Dim adjustmentRules() As TimeZoneInfo.AdjustmentRule = zone.GetAdjustmentRules()
         
         ' Indicate that time zone has no adjustment rules
         If adjustmentRules.Length = 0 Then
            Console.WriteLine("      No adjustment rules defined.")
         Else
            Console.WriteLine("      Adjustment Rules: {0}", adjustmentRules.Length)
            ' Iterate adjustment rules       
            For Each adjustmentRule In adjustmentRules
               Console.WriteLine("   Adjustment rule from {0:d} to {1:d}:", 
                                 adjustmentRule.DateStart, 
                                 adjustmentRule.DateEnd)                                 
               Console.WriteLine("      Delta: {0}", adjustmentRule.DaylightDelta)
               ' Get start of transition
               Dim daylightStart As TimeZoneInfo.TransitionTime = adjustmentRule.DaylightTransitionStart
               ' Display information on floating date rule
               If Not daylightStart.IsFixedDateRule Then
                  Console.WriteLine("      Begins at {0:t} on the {1} {2} of {3}", 
                                 daylightStart.TimeOfDay, 
                                 CType(daylightStart.Week, WeekOfMonth),  
                                 daylightStart.DayOfWeek, 
                                 dateInfo.GetMonthName(daylightStart.Month))
               ' Display information on fixed date rule 
               Else
                  Console.WriteLine("      Begins at {0:t} on {1} {2}", 
                                    daylightStart.TimeOfDay, 
                                    dateInfo.GetMonthName(daylightStart.Month), 
                                    daylightStart.Day)
               End If
               
               ' Get end of transition.
               Dim daylightEnd As TimeZoneInfo.TransitionTime = adjustmentRule.DaylightTransitionEnd
               ' Display information on floating date rule.
               If Not daylightEnd.IsFixedDateRule Then 
                  Console.WriteLine("      Ends at {0:t} on the {1} {2} of {3}", 
                                 daylightEnd.TimeOfDay, 
                                 CType(daylightEnd.Week, WeekOfMonth),  
                                 daylightEnd.DayOfWeek, 
                                 dateInfo.GetMonthName(daylightEnd.Month))
               ' Display information on fixed date rule.
               Else
                  Console.WriteLine("      Ends at {0:t} on {1} {2}", 
                                    daylightEnd.TimeOfDay, 
                                    dateInfo.GetMonthName(daylightEnd.Month), 
                                    daylightEnd.Day)
               End If
            Next
         End If   
      Next   
   End Sub

   Private Enum WeekOfMonth As Integer
      First = 1
      Second = 2
      Third = 3
      Fourth = 4
      Last = 5
   End Enum
End Module
' A portion of the output from the example might appear as follows:
'       Tonga Standard Time transition time information:
'          Time zone information:
'             Base UTC Offset: 13:00:00
'             Supports DST: False
'             No adjustment rules defined.
'       Samoa Standard Time transition time information:
'          Time zone information:
'             Base UTC Offset: 13:00:00
'             Supports DST: True
'             Adjustment Rules: 4
'          Adjustment rule from 1/1/0001 to 12/31/2009:
'             Delta: 00:00:00
'             Begins at 12:00 AM on January 1
'             Ends at 12:00 AM on January 1
'          Adjustment rule from 1/1/2010 to 12/31/2010:
'             Delta: 01:00:00
'             Begins at 11:59 PM on the Last Saturday of September
'             Ends at 12:00 AM on the First Friday of January
'          Adjustment rule from 1/1/2011 to 12/31/2011:
'             Delta: 01:00:00
'             Begins at 3:00 AM on the Fourth Saturday of September
'             Ends at 4:00 AM on the First Saturday of April
'          Adjustment rule from 1/1/2012 to 12/31/9999:
'             Delta: 01:00:00
'             Begins at 12:00 AM on the Last Sunday of September
'             Ends at 1:00 AM on the First Sunday of April
'       Line Islands Standard Time transition time information:
'          Time zone information:
'             Base UTC Offset: 14:00:00
'             Supports DST: False
'             No adjustment rules defined.

Commenti

Il valore della DateEnd proprietà è un valore di data senza un componente ora.

Poiché la data di fine della regola di rettifica corrente in genere non è nota, è possibile assegnare DateTime.MaxValue.Date alla DateEnd proprietà quando si crea una regola di regolazione personalizzata.

Importante

A meno che non esista un motivo interessante per eseguire questa operazione, è necessario definire la data di fine della regola di rettifica entro l'intervallo di tempo durante il quale il fuso orario osserva l'ora solare. A meno che non vi sia un motivo interessante per farlo, non è consigliabile definire la data di fine della regola di rettifica entro l'intervallo di tempo durante il quale il fuso orario osserva l'ora legale. Ad esempio, se la transizione di un fuso orario dall'ora legale si verifica la terza domenica di marzo e la transizione all'ora legale si verifica la prima domenica di ottobre, la data di fine effettiva della regola di rettifica non deve essere il 31 dicembre di un determinato anno, poiché tale data si verifica entro il periodo di ora legale.

Per impostazione predefinita, il Registro di sistema in Windows XP definisce una singola regola di rettifica la cui data di fine è venerdì 31 dicembre 9999 (valore di DateTime.MaxValue.Date), per ogni fuso orario. Per i fusi orari nel Stati Uniti, il Registro di sistema in Windows Vista definisce due regole di regolazione:

  • Da lunedì 01 gennaio 0001 a domenica 31 dicembre 2006.

  • Dal lunedì 01 gennaio 2007 al venerdì 31 dicembre 9999.

Ciò significa che, anche se le regole di regolazione del fuso orario archiviate nel Registro di sistema sono utili per eseguire le operazioni correnti relative al fuso orario, non possono essere usate in modo affidabile per il recupero delle informazioni sul fuso orario cronologico. Per informazioni sulla definizione di un fuso orario personalizzato con più regole di regolazione che possono essere usate in un'applicazione cronologica che riconosce il fuso orario, vedere Procedura: Creare fusi orari con regole di regolazione.

Si applica a