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TimeZoneInfo.TransitionTime Structure

Provides information about a specific time change, such as the change from daylight saving time to standard time or vice versa, in a particular time zone.

Namespace:  System
Assembly:  mscorlib (in mscorlib.dll)

[HostProtectionAttribute(SecurityAction.LinkDemand, MayLeakOnAbort = true)]
public struct TransitionTime : IEquatable<TimeZoneInfo..::..TransitionTime>, 
	ISerializable, IDeserializationCallback

The TimeZoneInfo.TransitionTime type exposes the following members.

Public propertyDayGets the day on which the time change occurs.
Public propertyDayOfWeekGets the day of the week on which the time change occurs.
Public propertyIsFixedDateRuleGets a value indicating whether the time change occurs at a fixed date and time (such as November 1) or a floating date and time (such as the last Sunday of October).
Public propertyMonthGets the month in which the time change occurs.
Public propertyTimeOfDayGets the hour, minute, and second at which the time change occurs.
Public propertyWeekGets the week of the month in which a time change occurs.

Public methodStatic memberCreateFixedDateRuleDefines a time change that uses a fixed-date rule.
Public methodStatic memberCreateFloatingDateRuleDefines a time change that uses a floating-date rule.
Public methodEquals(Object)Determines whether an object has identical values to the current TimeZoneInfo.TransitionTime object. (Overrides ValueType.Equals(Object).)
Public methodEquals(TimeZoneInfo.TransitionTime)Determines whether the current TimeZoneInfo.TransitionTime object has identical values to a second TimeZoneInfo.TransitionTime object.
Protected methodFinalizeAllows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
Public methodGetHashCodeServes as a hash function for hashing algorithms and data structures such as hash tables. (Overrides ValueType.GetHashCode().)
Public methodGetTypeGets the Type of the current instance. (Inherited from Object.)
Protected methodMemberwiseCloneCreates a shallow copy of the current Object. (Inherited from Object.)
Public methodToStringReturns the fully qualified type name of this instance. (Inherited from ValueType.)

Public operatorStatic memberEqualityDetermines whether two specified TimeZoneInfo.TransitionTime objects are equal.
Public operatorStatic memberInequalityDetermines whether two specified TimeZoneInfo.TransitionTime objects are not equal.

Explicit interface implemetationPrivate methodIDeserializationCallback.OnDeserializationInfrastructure. Runs when the deserialization of an object has been completed.
Explicit interface implemetationPrivate methodISerializable.GetObjectDataInfrastructure. Populates a SerializationInfo object with the data that is required to serialize this object.

You can use the TimeZoneInfo.TransitionTime structure to indicate when a transition from standard time to daylight saving time, or from daylight saving time back to standard time, occurs. This structure supports both fixed-date rules and floating-date rules. Use fixed-date rules for time transitions that occur on a specific day of a specific month (such as 2:00 A.M. on November 3). Use floating-date rules for time transitions that occur on a specific day of a specific week of a specific month (such as 2:00 A.M. on the first Sunday of November).


An instance of the TimeZoneInfo.TransitionTime structure is immutable. Once an object has been created, its values cannot be modified.

A TimeZoneInfo.TransitionTime object can be created by calling the static (Shared in Visual Basic) CreateFixedDateRule and CreateFloatingDateRule methods to create a fixed or floating-date rule, respectively. The starting and ending TimeZoneInfo.TransitionTime objects are then supplied as parameters to the CreateAdjustmentRule method to create a new adjustment rule that includes this transition time information.

The DaylightTransitionStart and DaylightTransitionEnd properties of an TimeZoneInfo.AdjustmentRule object return a TimeZoneInfo.TransitionTime object.


The HostProtectionAttribute attribute applied to this type or member has the following Resources property value: MayLeakOnAbort. The HostProtectionAttribute does not affect desktop applications (which are typically started by double-clicking an icon, typing a command, or entering a URL in a browser). For more information, see the HostProtectionAttribute class or SQL Server Programming and Host Protection Attributes.

.NET Framework

Supported in: 4, 3.5

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.