TimeZoneInfo.TransitionTime.CreateFloatingDateRule Method

public:
 static TimeZoneInfo::TransitionTime CreateFloatingDateRule(DateTime timeOfDay, int month, int week, DayOfWeek dayOfWeek);

public static TimeZoneInfo.TransitionTime CreateFloatingDateRule (DateTime timeOfDay, int month, int week, DayOfWeek dayOfWeek);

static member CreateFloatingDateRule : DateTime * int * int * DayOfWeek -> TimeZoneInfo.TransitionTime

Public Shared Function CreateFloatingDateRule (timeOfDay As DateTime, month As Integer, week As Integer, dayOfWeek As DayOfWeek) As TimeZoneInfo.TransitionTime

Parameters

Returns

Data about the time change.

Exceptions

Examples

The following example creates time zone transitions for an imaginary time zone by using both a fixed-date rule and a floating-date rule. The floating-date rule defines a time zone adjustment that starts at 2:00 A.M. on the last Sunday of March and ends at 3:00 A.M. on the fourth Sunday in October for the years 1956 onward.

// Declare necessary TimeZoneInfo.AdjustmentRule objects for time zone
TimeZoneInfo imaginaryTZ;
TimeSpan delta = new TimeSpan(1, 0, 0);
TimeZoneInfo.AdjustmentRule adjustment;
List<TimeZoneInfo.AdjustmentRule> adjustmentList = new List<TimeZoneInfo.AdjustmentRule>();
// Declare transition time variables to hold transition time information
TimeZoneInfo.TransitionTime transitionRuleStart, transitionRuleEnd;
                      
// Define a fictitious new time zone consisting of fixed and floating adjustment rules 
// Define fixed rule (for 1900-1955)
transitionRuleStart = TimeZoneInfo.TransitionTime.CreateFixedDateRule(new DateTime(1, 1, 1, 2, 0, 0), 3, 15);
transitionRuleEnd = TimeZoneInfo.TransitionTime.CreateFixedDateRule(new DateTime(1, 1, 1, 3, 0, 0), 11, 15);
adjustment = TimeZoneInfo.AdjustmentRule.CreateAdjustmentRule(new DateTime(1900, 1, 1), new DateTime(1955, 12, 31), 
             delta, transitionRuleStart, transitionRuleEnd);
adjustmentList.Add(adjustment);
// Define floating rule (for 1956- )
transitionRuleStart = TimeZoneInfo.TransitionTime.CreateFloatingDateRule(new DateTime(1, 1, 1, 2, 0, 0), 3, 5, DayOfWeek.Sunday);
transitionRuleEnd = TimeZoneInfo.TransitionTime.CreateFloatingDateRule(new DateTime(1, 1, 1, 3, 0, 0), 10, 4, DayOfWeek.Sunday); 
adjustment = TimeZoneInfo.AdjustmentRule.CreateAdjustmentRule(new DateTime(1956, 1, 1), DateTime.MaxValue.Date, delta, transitionRuleStart, transitionRuleEnd);
adjustmentList.Add(adjustment); 

// Create fictitious time zone   
imaginaryTZ = TimeZoneInfo.CreateCustomTimeZone("Fictitious Standard Time", new TimeSpan(-9, 0, 0), 
                "(GMT-09:00) Fictitious Time", "Fictitious Standard Time", 
                "Fictitious Daylight Time", adjustmentList.ToArray());

let delta = TimeSpan(1, 0, 0)
let adjustmentList = ResizeArray()
                    
// Define a fictitious new time zone consisting of fixed and floating adjustment rules 
// Define fixed rule (for 1900-1955)
let transitionRuleStart = TimeZoneInfo.TransitionTime.CreateFixedDateRule(DateTime(1, 1, 1, 2, 0, 0), 3, 15)
let transitionRuleEnd = TimeZoneInfo.TransitionTime.CreateFixedDateRule(DateTime(1, 1, 1, 3, 0, 0), 11, 15)
let adjustment = 
    TimeZoneInfo.AdjustmentRule.CreateAdjustmentRule(DateTime(1900, 1, 1), DateTime(1955, 12, 31), delta, transitionRuleStart, transitionRuleEnd)
adjustmentList.Add adjustment
// Define floating rule (for 1956- )
let transitionRuleStart = TimeZoneInfo.TransitionTime.CreateFloatingDateRule(DateTime(1, 1, 1, 2, 0, 0), 3, 5, DayOfWeek.Sunday)
let transitionRuleEnd = TimeZoneInfo.TransitionTime.CreateFloatingDateRule(DateTime(1, 1, 1, 3, 0, 0), 10, 4, DayOfWeek.Sunday) 
let adjustment = TimeZoneInfo.AdjustmentRule.CreateAdjustmentRule(DateTime(1956, 1, 1), DateTime.MaxValue.Date, delta, transitionRuleStart, transitionRuleEnd)
adjustmentList.Add adjustment 

// Create fictitious time zone   
let imaginaryTZ = 
    TimeZoneInfo.CreateCustomTimeZone("Fictitious Standard Time", TimeSpan(-9, 0, 0), 
                "(GMT-09:00) Fictitious Time", "Fictitious Standard Time", 
                "Fictitious Daylight Time", adjustmentList.ToArray())

' Declare necessary TimeZoneInfo.AdjustmentRule objects for time zone
Dim imaginaryTZ As TimeZoneInfo
Dim delta As New TimeSpan(1, 0, 0)
Dim adjustment As TimeZoneInfo.AdjustmentRule
Dim adjustmentList As New List(Of TimeZoneInfo.AdjustmentRule)
' Declare transition time variables to hold transition time information
Dim transitionRuleStart, transitionRuleEnd As TimeZoneInfo.TransitionTime
                      
' Define a fictitious new time zone consisting of fixed and floating adjustment rules 
' Define fixed rule (for 1900-1955)
transitionRuleStart = TimeZoneInfo.TransitionTime.CreateFixedDateRule(#2:00:00AM#, 3, 15)
transitionRuleEnd = TimeZoneInfo.TransitionTime.CreateFixedDateRule(#3:00:00AM#, 11, 15)
adjustment = TimeZoneInfo.AdjustmentRule.CreateAdjustmentRule(#1/1/1900#, #12/31/1955#, delta, _
             transitionRuleStart, transitionRuleEnd)
adjustmentList.Add(adjustment)
' Define floating rule (for 1956- )
transitionRuleStart = TimeZoneInfo.TransitionTime.CreateFloatingDateRule(#02:00:00AM#, 3, 5, DayOfWeek.Sunday)
transitionRuleEnd = TimeZoneInfo.TransitionTime.CreateFloatingDateRule(#03:00:00AM#, 10, 4, DayOfWeek.Sunday) 
adjustment = TimeZoneInfo.AdjustmentRule.CreateAdjustmentRule(#01/01/1956#, Date.MaxValue.Date, delta, transitionRuleStart, transitionRuleEnd)
adjustmentList.Add(adjustment) 

' Create fictitious time zone   
imaginaryTZ = TimeZoneInfo.CreateCustomTimeZone("Fictitious Standard Time", New TimeSpan(-9, 0, 0), _
                "(GMT-09:00) Fictitious Time", "Fictitious Standard Time", _
                "Fictitious Daylight Time", adjustmentList.ToArray())

Remarks

This method creates a floating-date rule (that is, a time change that occurs on a specific day of a specific week of a specific month). For example, a time change that occurs on the last Sunday of October follows a floating-date rule.

For transitions from standard time to daylight saving time, the timeOfDay argument 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. Note that this is a DateTime value whose year, month, and date values must all equal 1.

Applies to