TimeZoneInfo.GetAdjustmentRules メソッド

定義

現在の TimeZoneInfo オブジェクトに適用する TimeZoneInfo.AdjustmentRule オブジェクトの配列を取得します。

public:
 cli::array <TimeZoneInfo::AdjustmentRule ^> ^ GetAdjustmentRules();
public TimeZoneInfo.AdjustmentRule[] GetAdjustmentRules ();
member this.GetAdjustmentRules : unit -> TimeZoneInfo.AdjustmentRule[]
Public Function GetAdjustmentRules () As TimeZoneInfo.AdjustmentRule()

戻り値

AdjustmentRule[]

このタイム ゾーンのオブジェクトの配列。

例外

システムには、調整規則のメモリ内コピーを作成するのに十分なメモリがありません。

次の例では、ローカル システムで定義されているすべてのタイム ゾーンを取得し、調整規則に関する完全な情報をコンソールに表示します。

private enum WeekOfMonth 
{
   First = 1,
   Second = 2,
   Third = 3,
   Fourth = 4,
   Last = 5,
}

private static void ShowStartAndEndDates()
{
   // Get all time zones from system
   ReadOnlyCollection<TimeZoneInfo> timeZones = TimeZoneInfo.GetSystemTimeZones();
   string[] monthNames = CultureInfo.CurrentCulture.DateTimeFormat.MonthNames;
   // Get each time zone
   foreach (TimeZoneInfo timeZone in timeZones)
   {
      TimeZoneInfo.AdjustmentRule[] adjustments = timeZone.GetAdjustmentRules();
      // Display message for time zones with no adjustments
      if (adjustments.Length == 0)
      {
         Console.WriteLine("{0} has no adjustment rules", timeZone.StandardName);
      }   
      else
      {
         // Handle time zones with 1 or 2+ adjustments differently
         bool showCount = false;
         int ctr = 0;
         string spacer = "";
         
         Console.WriteLine("{0} Adjustment rules", timeZone.StandardName);
         if (adjustments.Length > 1)
         {
            showCount = true;
            spacer = "   ";
         }   
         // Iterate adjustment rules
         foreach (TimeZoneInfo.AdjustmentRule adjustment in adjustments)
         {
            if (showCount)
            { 
               Console.WriteLine("   Adjustment rule #{0}", ctr+1);
               ctr++;
            }
            // Display general adjustment information
            Console.WriteLine("{0}   Start Date: {1:D}", spacer, adjustment.DateStart);
            Console.WriteLine("{0}   End Date: {1:D}", spacer, adjustment.DateEnd);
            Console.WriteLine("{0}   Time Change: {1}:{2:00} hours", spacer, 
                              adjustment.DaylightDelta.Hours, adjustment.DaylightDelta.Minutes);
            // Get transition start information
            TimeZoneInfo.TransitionTime transitionStart = adjustment.DaylightTransitionStart;
            Console.Write("{0}   Annual Start: ", spacer);
            if (transitionStart.IsFixedDateRule)
            {
               Console.WriteLine("On {0} {1} at {2:t}", 
                                 monthNames[transitionStart.Month - 1], 
                                 transitionStart.Day, 
                                 transitionStart.TimeOfDay);
            }
            else
            {
               Console.WriteLine("The {0} {1} of {2} at {3:t}", 
                                 ((WeekOfMonth)transitionStart.Week).ToString(), 
                                 transitionStart.DayOfWeek.ToString(), 
                                 monthNames[transitionStart.Month - 1], 
                                 transitionStart.TimeOfDay);
            }
            // Get transition end information
            TimeZoneInfo.TransitionTime transitionEnd = adjustment.DaylightTransitionEnd;
            Console.Write("{0}   Annual End: ", spacer);
            if (transitionEnd.IsFixedDateRule)
            {
               Console.WriteLine("On {0} {1} at {2:t}", 
                                 monthNames[transitionEnd.Month - 1], 
                                 transitionEnd.Day, 
                                 transitionEnd.TimeOfDay);
            }
            else
            {
               Console.WriteLine("The {0} {1} of {2} at {3:t}", 
                                 ((WeekOfMonth)transitionEnd.Week).ToString(), 
                                 transitionEnd.DayOfWeek.ToString(), 
                                 monthNames[transitionEnd.Month - 1], 
                                 transitionEnd.TimeOfDay);
            }
         }
      }   
      Console.WriteLine();
   } 
}
type WeekOfMonth = 
    | First = 1
    | Second = 2
    | Third = 3
    | Fourth = 4
    | Last = 5

let showStartAndEndDates () =
    // Get all time zones from system
    let timeZones = TimeZoneInfo.GetSystemTimeZones()
    let monthNames = CultureInfo.CurrentCulture.DateTimeFormat.MonthNames
    // Get each time zone
    for timeZone in timeZones do
        let adjustments = timeZone.GetAdjustmentRules()
        // Display message for time zones with no adjustments
        if adjustments.Length = 0 then
            printfn $"{timeZone.StandardName} has no adjustment rules"
        else
            // Handle time zones with 1 or 2+ adjustments differently
            let mutable ctr = 0
            let showCount, spacer = 
                if adjustments.Length > 1 then
                    true, "   "
                else 
                    false, ""
            printfn $"{timeZone.StandardName} Adjustment rules"

            // Iterate adjustment rules
            for adjustment in adjustments do
                if showCount then
                    printfn $"   Adjustment rule #{ctr + 1}"
                    ctr <- ctr + 1
                // Display general adjustment information
                printfn $"{spacer}   Start Date: {adjustment.DateStart:D}"
                printfn $"{spacer}   End Date: {adjustment.DateEnd:D}"
                printfn $"{spacer}   Time Change: {adjustment.DaylightDelta.Hours}:{adjustment.DaylightDelta.Minutes:D2} hours"
                // Get transition start information
                let transitionStart = adjustment.DaylightTransitionStart
                printf $"{spacer}   Annual Start: "
                if transitionStart.IsFixedDateRule then
                    printfn $"On {monthNames[transitionStart.Month - 1]} {transitionStart.Day} at {transitionStart.TimeOfDay:t}"
                else
                    printfn $"The {transitionStart.Week |> enum<WeekOfMonth>} {transitionStart.DayOfWeek} of {monthNames[transitionStart.Month - 1]} at {transitionStart.TimeOfDay:t}"
                // Get transition end information
                let transitionEnd = adjustment.DaylightTransitionEnd
                printf $"{spacer}   Annual End: "
                if transitionEnd.IsFixedDateRule then
                    printfn $"On {monthNames[transitionEnd.Month - 1]} {transitionEnd.Day} at {transitionEnd.TimeOfDay:t}"
                else
                    printfn $"The {enum<WeekOfMonth> transitionEnd.Week} {transitionEnd.DayOfWeek} of {monthNames[transitionEnd.Month - 1]} at {transitionEnd.TimeOfDay:t}" 
        Console.WriteLine()
Private Enum WeekOfMonth As Integer
   First = 1
   Second = 2
   Third = 3
   Fourth = 4
   Last = 5
End Enum

Private Sub ShowStartAndEndDates()
   ' Get all time zones from system
   Dim timeZones As ReadOnlyCollection(Of TimeZoneInfo) = TimeZoneInfo.GetSystemTimeZones()
   ' Get each time zone
   For Each timeZone As TimeZoneInfo In timeZones
      Dim adjustments() As TimeZoneInfo.AdjustmentRule = timeZone.GetAdjustmentRules()
      ' Display message for time zones with no adjustments
      If adjustments.Length = 0 Then
         Console.WriteLine("{0} has no adjustment rules", timeZone.StandardName)
      Else
         ' Handle time zones with 1 or 2+ adjustments differently
         Dim showCount As Boolean = False
         Dim ctr As Integer = 0
         Dim spacer As String = ""
         
         Console.WriteLine("{0} Adjustment rules", timeZone.StandardName)
         If adjustments.Length > 1 Then showCount = True : spacer = "   "  
         ' Iterate adjustment rules
         For Each adjustment As TimeZoneInfo.AdjustmentRule in adjustments
            If showCount Then 
               Console.WriteLine("   Adjustment rule #{0}", ctr+1)
               ctr += 1
            End If
            ' Display general adjustment information
            Console.WriteLine("{0}   Start Date: {1:D}", spacer, adjustment.DateStart)
            Console.WriteLine("{0}   End Date: {1:D}", spacer, adjustment.DateEnd)
            Console.WriteLine("{0}   Time Change: {1}:{2:00} hours", spacer, _
                              adjustment.DaylightDelta.Hours, adjustment.DaylightDelta.Minutes)
            ' Get transition start information
            Dim transitionStart As TimeZoneInfo.TransitionTime = adjustment.DaylightTransitionStart
            Console.Write("{0}   Annual Start: ", spacer)
            If transitionStart.IsFixedDateRule Then
               Console.WriteLine("On {0} {1} at {2:t}", _
                                 MonthName(transitionStart.Month), _
                                 transitionStart.Day, _
                                 transitionStart.TimeOfDay)
            Else
               Console.WriteLine("The {0} {1} of {2} at {3:t}", _
                                 CType(transitionStart.Week, WeekOfMonth).ToString(), _
                                 transitionStart.DayOfWeek.ToString(), _
                                 MonthName(transitionStart.Month), _
                                 transitionStart.TimeOfDay)
            End If
            ' Get transition end information
            Dim transitionEnd As TimeZoneInfo.TransitionTime = adjustment.DaylightTransitionEnd
                              
            Console.Write("{0}   Annual End: ", spacer)
            If transitionEnd.IsFixedDateRule Then
               Console.WriteLine("On {0} {1} at {2:t}", _
                                 MonthName(transitionEnd.Month), _
                                 transitionEnd.Day, _
                                 transitionEnd.TimeOfDay)
            Else
               Console.WriteLine("The {0} {1} of {2} at {3:t}", _
                                 CType(transitionEnd.Week, WeekOfMonth).ToString(), _
                                 transitionEnd.DayOfWeek.ToString(), _
                                 MonthName(transitionEnd.Month), _
                                 transitionEnd.TimeOfDay)
            End If
         Next
      End If   
      Console.WriteLine()
   Next 
End Sub

注釈

このメソッドは GetAdjustmentRules 、オブジェクトの System.TimeZoneInfo.AdjustmentRule 配列を取得します。 配列内の各オブジェクトは、そのタイム ゾーン調整の有効な開始日と終了日と、その差分 (調整によって時間が変更される正確な量) を定義します。 さらに、2 つのプロパティは、標準時との間の各年の切り替えがいつ発生するかを定義するオブジェクトを返 System.TimeZoneInfo.TransitionTime します。

タイム ゾーンに複数の調整規則がある場合、通常、最も早い (インデックス 0) から最新 (インデックス Length - 1) に順序付けされます。

タイム ゾーンに調整規則がない場合、 GetAdjustmentRules メソッドは空の配列 (0 の配列 Length ) を返します。

メソッドによって GetAdjustmentRules 返される配列の要素に対する変更は、特定のタイム ゾーンに属する調整規則には反映されません。 タイム ゾーンの調整規則 (夏時間との間の過去の切り替えを反映するなど) を変更するには、既存の調整規則を変更するのではなく、適切な調整規則を使用して新しいタイム ゾーンを作成する必要があります。

適用対象

こちらもご覧ください