TimeZoneInfo.AdjustmentRule Class
Definition
Important
Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.
Provides information about a time zone adjustment, such as the transition to and from daylight saving time.
public: ref class TimeZoneInfo::AdjustmentRule sealed : IEquatable<TimeZoneInfo::AdjustmentRule ^>, System::Runtime::Serialization::IDeserializationCallback, System::Runtime::Serialization::ISerializable
public sealed class TimeZoneInfo.AdjustmentRule : IEquatable<TimeZoneInfo.AdjustmentRule>, System.Runtime.Serialization.IDeserializationCallback, System.Runtime.Serialization.ISerializable
[System.Serializable]
public sealed class TimeZoneInfo.AdjustmentRule : IEquatable<TimeZoneInfo.AdjustmentRule>, System.Runtime.Serialization.IDeserializationCallback, System.Runtime.Serialization.ISerializable
type TimeZoneInfo.AdjustmentRule = class
interface IEquatable<TimeZoneInfo.AdjustmentRule>
interface IDeserializationCallback
interface ISerializable
type TimeZoneInfo.AdjustmentRule = class
interface IDeserializationCallback
interface ISerializable
interface IEquatable<TimeZoneInfo.AdjustmentRule>
[<System.Serializable>]
type TimeZoneInfo.AdjustmentRule = class
interface IEquatable<TimeZoneInfo.AdjustmentRule>
interface ISerializable
interface IDeserializationCallback
Public NotInheritable Class TimeZoneInfo.AdjustmentRule
Implements IDeserializationCallback, IEquatable(Of TimeZoneInfo.AdjustmentRule), ISerializable
- Inheritance
-
TimeZoneInfo.AdjustmentRule
- Attributes
- Implements
Examples
The following example retrieves all time zones defined on the local system and displays complete information about their adjustment rules.
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
The following is a small portion of the output that is generated by the example. The exact output will vary depending on the operating system and the date on which the example is run.
Morocco Standard Time Adjustment rules
Adjustment rule #1
Start Date: Tuesday, January 01, 2008
End Date: Wednesday, December 31, 2008
Time Change: 1:00 hours
Annual Start: The Last Saturday of May at 11:59 PM
Annual End: The Last Sunday of August at 11:59 PM
Adjustment rule #2
Start Date: Thursday, January 01, 2009
End Date: Thursday, December 31, 2009
Time Change: 1:00 hours
Annual Start: The Last Sunday of May at 11:59 PM
Annual End: The Third Thursday of August at 11:59 PM
Coordinated Universal Time has no adjustment rules
GMT Standard Time Adjustment rules
Start Date: Monday, January 01, 0001
End Date: Friday, December 31, 9999
Time Change: 1:00 hours
Annual Start: The Last Sunday of March at 1:00 AM
Annual End: The Last Sunday of October at 2:00 AM
Greenwich Standard Time has no adjustment rules
W. Europe Standard Time Adjustment rules
Start Date: Monday, January 01, 0001
End Date: Friday, December 31, 9999
Time Change: 1:00 hours
Annual Start: The Last Sunday of March at 2:00 AM
Annual End: The Last Sunday of October at 3:00 AM
Central Europe Standard Time Adjustment rules
Start Date: Monday, January 01, 0001
End Date: Friday, December 31, 9999
Time Change: 1:00 hours
Annual Start: The Last Sunday of March at 2:00 AM
Annual End: The Last Sunday of October at 3:00 AM
Romance Standard Time Adjustment rules
Start Date: Monday, January 01, 0001
End Date: Friday, December 31, 9999
Time Change: 1:00 hours
Annual Start: The Last Sunday of March at 2:00 AM
Annual End: The Last Sunday of October at 3:00 AM
Central European Standard Time Adjustment rules
Start Date: Monday, January 01, 0001
End Date: Friday, December 31, 9999
Time Change: 1:00 hours
Annual Start: The Last Sunday of March at 2:00 AM
Annual End: The Last Sunday of October at 3:00 AM
W. Central Africa Standard Time has no adjustment rules
Remarks
The TimeZoneInfo.AdjustmentRule class defines the effective start and end dates of a particular time change to and from daylight saving time, respectively, as well as its delta (the exact amount by which the adjustment causes the time zone's standard time to change). In addition, two properties return TimeZoneInfo.TransitionTime objects that define when each transition to and from standard time occurs.
Note
An instance of the TimeZoneInfo.AdjustmentRule class is immutable. Once an object has been created, its values cannot be modified.
To create a TimeZoneInfo.AdjustmentRule object, call the static
(Shared
in Visual Basic) TimeZoneInfo.AdjustmentRule.CreateAdjustmentRule method. You can then supply an array of TimeZoneInfo.AdjustmentRule objects to two of the overloads of the TimeZoneInfo.CreateCustomTimeZone method. To retrieve the adjustment rules of a particular time zone, call its TimeZoneInfo.GetAdjustmentRules method, which returns an array of TimeZoneInfo.AdjustmentRule objects.
Properties
BaseUtcOffsetDelta |
Gets the time difference with the base UTC offset for the time zone during the adjustment-rule period. |
DateEnd |
Gets the date when the adjustment rule ceases to be in effect. |
DateStart |
Gets the date when the adjustment rule takes effect. |
DaylightDelta |
Gets the amount of time that is required to form the time zone's daylight saving time. This amount of time is added to the time zone's offset from Coordinated Universal Time (UTC). |
DaylightTransitionEnd |
Gets information about the annual transition from daylight saving time back to standard time. |
DaylightTransitionStart |
Gets information about the annual transition from standard time to daylight saving time. |
Methods
CreateAdjustmentRule(DateTime, DateTime, TimeSpan, TimeZoneInfo+TransitionTime, TimeZoneInfo+TransitionTime) |
Creates a new adjustment rule for a particular time zone. |
CreateAdjustmentRule(DateTime, DateTime, TimeSpan, TimeZoneInfo+TransitionTime, TimeZoneInfo+TransitionTime, TimeSpan) |
Creates a new adjustment rule for a particular time zone. |
Equals(Object) |
Indicates whether the current instance is equal to another instance. |
Equals(Object) |
Determines whether the specified object is equal to the current object. (Inherited from Object) |
Equals(TimeZoneInfo+AdjustmentRule) |
Determines whether the current TimeZoneInfo.AdjustmentRule object is equal to a second TimeZoneInfo.AdjustmentRule object. |
GetHashCode() |
Serves as a hash function for hashing algorithms and data structures such as hash tables. |
GetType() |
Gets the Type of the current instance. (Inherited from Object) |
MemberwiseClone() |
Creates a shallow copy of the current Object. (Inherited from Object) |
ToString() |
Returns a string that represents the current object. (Inherited from Object) |
Explicit Interface Implementations
IDeserializationCallback.OnDeserialization(Object) |
Runs when the deserialization of a TimeZoneInfo.AdjustmentRule object is completed. |
ISerializable.GetObjectData(SerializationInfo, StreamingContext) |
Populates a SerializationInfo object with the data that is required to serialize this object. |
Applies to
See also
.NET