TimeZoneInfo.TransitionTime.TimeOfDay Property

Definition

Namespace:

System

Assembly:

System.Runtime.dll

Source:

TimeZoneInfo.TransitionTime.cs

Gets the hour, minute, and second at which the time change occurs.

public:
 property DateTime TimeOfDay { DateTime get(); };

public DateTime TimeOfDay { get; }

member this.TimeOfDay : DateTime

Public ReadOnly Property TimeOfDay As DateTime

Property Value

DateTime

The time of day at which the time change occurs.

Examples

The following example enumerates the time zones found on the local computer and displays transition time information for those time zones that have adjustment rules. The time information includes the time of day at which the time change occurs.

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

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

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

let getAllTransitionTimes () =
    let timeZones = TimeZoneInfo.GetSystemTimeZones()
    let dateInfo = CultureInfo.CurrentCulture.DateTimeFormat
    
    for zone in timeZones do
        printfn $"{zone.StandardName} transition time information:"
        let adjustmentRules= zone.GetAdjustmentRules()
        
        // Indicate that time zone has no adjustment rules
        if adjustmentRules.Length = 0 then
            printfn "   No adjustment rules defined."
        else
            // Iterate adjustment rules       
            for adjustmentRule in adjustmentRules do
                printfn $"   Adjustment rule from {adjustmentRule.DateStart:d} to {adjustmentRule.DateEnd:d}:"                                 
                
                // Get start of transition
                let daylightStart = adjustmentRule.DaylightTransitionStart
                // Display information on fixed 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 floating date rule 
                else
                    printfn $"      Begins at {daylightStart.TimeOfDay:t} on the {enum<WeekOfMonth> daylightStart.Week} {daylightStart.DayOfWeek} of {dateInfo.GetMonthName daylightStart.Month}."
                
                // Get end of transition
                let daylightEnd = adjustmentRule.DaylightTransitionEnd
                // Display information on fixed 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 floating date rule
                else
                    printfn $"      Ends at {daylightStart.TimeOfDay:t} on the {enum<WeekOfMonth> daylightStart.Week} {daylightStart.DayOfWeek} of {dateInfo.GetMonthName daylightStart.Month}."

Private Enum WeekOfMonth As Integer
   First = 1
   Second = 2
   Third = 3
   Fourth = 4
   Last = 5 
End Enum

Sub GetAllTransitionTimes()
   Dim timeZones As ReadOnlyCollection(Of TimeZoneInfo) = TimeZoneInfo.GetSystemTimeZones()
   For Each zone As TimeZoneInfo In timeZones
      Console.WriteLine("{0} transition time information:", zone.StandardName)
      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
         ' Iterate adjustment rules       
         For Each adjustmentRule As TimeZoneInfo.AdjustmentRule in adjustmentRules
            Console.WriteLine("   Adjustment rule from {0:d} to {1:d}:", _
                              adjustmentRule.DateStart, _
                              adjustmentRule.DateEnd)                                 
            
            ' Get start of transition
            Dim daylightStart As TimeZoneInfo.TransitionTime = adjustmentRule.DaylightTransitionStart
            ' Display information on fixed 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).ToString(), _ 
                              daylightStart.DayOfWeek.ToString(), _
                              MonthName(daylightStart.Month))
            ' Display information on floating date rule 
            Else
               Console.WriteLine("      Begins at {0:t} on the {1} {2} of {3}.", _
                                 daylightStart.TimeOfDay, _
                                 CType(daylightStart.Week, WeekOfMonth).ToString(), _ 
                                 daylightStart.DayOfWeek.ToString(), _
                                 MonthName(daylightStart.Month))
            End If
            
            ' Get end of transition
            Dim daylightEnd As TimeZoneInfo.TransitionTime = adjustmentRule.DaylightTransitionEnd
            ' Display information on fixed 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).ToString(), _ 
                              daylightEnd.DayOfWeek.ToString(), _
                              MonthName(daylightEnd.Month))
            ' Display information on floating date rule
            Else
               Console.WriteLine("      Ends at {0:t} on the {1} {2} of {3}.", _
                                 daylightStart.TimeOfDay, _
                                 CType(daylightStart.Week, WeekOfMonth).ToString(), _ 
                                 daylightStart.DayOfWeek.ToString(), _
                                 MonthName(daylightStart.Month))
            End If                     
         Next
      End If   
   Next   
End Sub

Remarks

For transitions from standard time to daylight saving time, the TimeOfDay value represents the time of the transition in the time zone's standard time. For transitions from daylight saving time to standard time, it represents the time of the transition in the time zone's daylight saving time.

The TimeOfDay property defines only the time of a time change, but not its date. The date is determined by the Month and Day properties for fixed-rule changes, and by the Month, Week, and DayOfWeek properties for floating-rule changes. The date component of this DateTime value is ignored; the value of the year, month, and day is always 1.

The TimeOfDay property is used for both fixed-date and floating-date transitions.