TimeZoneInfo.FromSerializedString Method (String)


Deserializes a string to re-create an original serialized TimeZoneInfo object.

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

Public Shared Function FromSerializedString (
	source As String
) As TimeZoneInfo


Type: System.String

The string representation of the serialized TimeZoneInfo object.

Return Value

Type: System.TimeZoneInfo

The original serialized object.

Exception Condition

The source parameter is String.Empty.


The source parameter is a null string.


The source parameter cannot be deserialized back into a TimeZoneInfo object.

There is an alternative to providing all the code required to create a time zone that is not found in the registry. You can define a custom time zone and either use the ToSerializedString method in a standalone executable or use an application's setup program to save the time zone as a string. The application can then retrieve this string from its storage location and instantiate it using the FromSerializedString method.

The following example tries to retrieve the Antarctica/South Pole time zone from the local system. If it fails, the code tries to retrieve information about the time zone from a text file in the application directory. If this attempt fails, the code creates the time zone and writes information about the time zone to the text file.

Private Function InitializeTimeZone() As TimeZoneInfo
   Dim southPole As TimeZoneInfo = Nothing
   ' Determine if South Pole time zone is defined in system
      southPole = TimeZoneInfo.FindSystemTimeZoneById("Antarctica/South Pole Standard Time")
   ' Time zone does not exist; create it, store it in a text file, and return it
   Catch e As TimeZoneNotFoundException
      Dim found As Boolean
      Const filename As String = ".\TimeZoneInfo.txt"

      If File.Exists(filename) Then
         Dim reader As StreamReader = New StreamReader(fileName)
         Dim timeZoneString As String
         Do While reader.Peek() >= 0
            timeZoneString = reader.ReadLine()
            If timeZoneString.Contains("Antarctica/South Pole") Then
               southPole = TimeZoneInfo.FromSerializedString(timeZoneString)
               found = True
               Exit Do
            End If   
      End If
      If Not found Then               
         ' Define transition times to/from DST
         Dim startTransition As TimeZoneInfo.TransitionTime = TimeZoneInfo.TransitionTime.CreateFloatingDateRule(#02:00:00#, 10, 1, DayOfWeek.Sunday) 
         Dim endTransition As TimeZoneInfo.TransitionTime = TimeZoneInfo.TransitionTime.CreateFloatingDateRule(#02:00:00#, 3, 3, DayOfWeek.Sunday)
         ' Define adjustment rule
         Dim delta As TimeSpan = New TimeSpan(1, 0, 0)
         Dim adjustment As TimeZoneInfo.AdjustmentRule = TimeZoneInfo.AdjustmentRule.CreateAdjustmentRule(#10/01/1989#, Date.MaxValue.Date, delta, startTransition, endTransition)
         ' Create array for adjustment rules
         Dim adjustments() As TimeZoneInfo.AdjustmentRule = {adjustment}
         ' Define other custom time zone arguments
         Dim displayName As String = "(GMT+12:00) Antarctica/South Pole"
         Dim standardName As String = "Antarctica/South Pole Standard Time"
         Dim daylightName As String = "Antarctica/South Pole Daylight Time"
         Dim offset As TimeSpan = New TimeSpan(12, 0, 0)
         southPole = TimeZoneInfo.CreateCustomTimeZone(standardName, offset, displayName, standardName, daylightName, adjustments)
         ' Write time zone to the file
         Dim writer As StreamWriter = New StreamWriter(filename, True)
      End If
   End Try
   Return southPole
End Function

.NET Framework
Available since 3.5
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