DateTime.SpecifyKind Method

July 28, 2014

Creates a new DateTime object that has the same number of ticks as the specified DateTime, but is designated as either local time, Coordinated Universal Time (UTC), or neither, as indicated by the specified DateTimeKind value.

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

'Declaration
Public Shared Function SpecifyKind ( _
	value As DateTime, _
	kind As DateTimeKind _
) As DateTime

Parameters

value
Type: System.DateTime
The date and time value for the new object.
kind
Type: System.DateTimeKind
One of the enumeration values that specifies whether the new object will be designated in local time, in UTC, or neither.

Return Value

Type: System.DateTime
A new object that has the same number of ticks as the object represented by the value parameter and the DateTimeKind value specified by the kind parameter.

A DateTime object consists of a Kind field that indicates whether the time value is based on local time, Coordinated Universal Time (UTC), or neither, and a Ticks field that contains a time value measured in 100-nanosecond ticks. The SpecifyKind method creates a new DateTime object using the specified kind parameter and the original time value.

Important noteImportant Note:

The returned DateTime value does not represent the same instant in time as the value parameter, and SpecifyKind is not a time zone conversion method. Instead, it leaves the time specified by the value parameter unchanged, and sets the Kind property to kind.

The SpecifyKind method is useful in interoperability scenarios where you receive a DateTime object with an unspecified Kind field, but you can determine by independent means that the Ticks field represents local time or UTC.

The following example uses the SpecifyKind method to demonstrate how the Kind property influences the ToLocalTime and ToUniversalTime conversion methods.



' This code example demonstrates the DateTime Kind, Now, and
' UtcNow properties, and the SpecifyKind(), ToLocalTime(), 
' and ToUniversalTime() methods.

Class Example
   Public Shared Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)
      ' Get the date and time for the current moment, adjusted 
      ' to the local time zone.
      Dim saveNow As DateTime = DateTime.Now

      ' Get the date and time for the current moment expressed 
      ' as coordinated universal time (UTC).
      Dim saveUtcNow As DateTime = DateTime.UtcNow
      Dim myDt As DateTime

      ' Display the value and Kind property of the current moment 
      ' expressed as UTC and local time.
      DisplayNow(outputBlock, "UtcNow: ..........", saveUtcNow)
      DisplayNow(outputBlock, "Now: .............", saveNow)
      outputBlock.Text &= vbCrLf

      ' Change the Kind property of the current moment to 
      ' DateTimeKind.Utc and display the result.
      myDt = DateTime.SpecifyKind(saveNow, DateTimeKind.Utc)
      Display(outputBlock, "Utc: .............", myDt)

      ' Change the Kind property of the current moment to 
      ' DateTimeKind.Local and display the result.
      myDt = DateTime.SpecifyKind(saveNow, DateTimeKind.Local)
      Display(outputBlock, "Local: ...........", myDt)

      ' Change the Kind property of the current moment to 
      ' DateTimeKind.Unspecified and display the result.
      myDt = DateTime.SpecifyKind(saveNow, DateTimeKind.Unspecified)
      Display(outputBlock, "Unspecified: .....", myDt)
   End Sub 'Main

   ' Display the value and Kind property of a DateTime structure, the 
   ' DateTime structure converted to local time, and the DateTime 
   ' structure converted to universal time. 

   Public Shared datePatt As String = "M/d/yyyy hh:mm:ss tt"

   Public Shared Sub Display(ByVal outputBlock As System.Windows.Controls.TextBlock, ByVal title As String, ByVal inputDt As DateTime)
      Dim dispDt As DateTime = inputDt
      Dim dtString As String

      ' Display the original DateTime.
      dtString = dispDt.ToString(datePatt)
      outputBlock.Text += String.Format("{0} {1}, Kind = {2}", title, dtString, dispDt.Kind) & vbCrLf

      ' Convert inputDt to local time and display the result. 
      ' If inputDt.Kind is DateTimeKind.Utc, the conversion is performed.
      ' If inputDt.Kind is DateTimeKind.Local, the conversion is not performed.
      ' If inputDt.Kind is DateTimeKind.Unspecified, the conversion is 
      ' performed as if inputDt was universal time.
      dispDt = inputDt.ToLocalTime()
      dtString = dispDt.ToString(datePatt)
      outputBlock.Text += String.Format("  ToLocalTime:     {0}, Kind = {1}", dtString, dispDt.Kind) & vbCrLf

      ' Convert inputDt to universal time and display the result. 
      ' If inputDt.Kind is DateTimeKind.Utc, the conversion is not performed.
      ' If inputDt.Kind is DateTimeKind.Local, the conversion is performed.
      ' If inputDt.Kind is DateTimeKind.Unspecified, the conversion is 
      ' performed as if inputDt was local time.
      dispDt = inputDt.ToUniversalTime()
      dtString = dispDt.ToString(datePatt)
      outputBlock.Text += String.Format("  ToUniversalTime: {0}, Kind = {1}", dtString, dispDt.Kind) & vbCrLf
      outputBlock.Text &= vbCrLf
   End Sub 'Display


   ' Display the value and Kind property for DateTime.Now and DateTime.UtcNow.

   Public Shared Sub DisplayNow(ByVal outputBlock As System.Windows.Controls.TextBlock, ByVal title As String, ByVal inputDt As DateTime)
      Dim dtString As String = inputDt.ToString(datePatt)
      outputBlock.Text += String.Format("{0} {1}, Kind = {2}", title, dtString, inputDt.Kind) & vbCrLf
   End Sub 'DisplayNow
End Class 'Sample

'
'This code example produces the following results:
'
'UtcNow: .......... 5/6/2005 09:34:42 PM, Kind = Utc
'Now: ............. 5/6/2005 02:34:42 PM, Kind = Local
'
'Utc: ............. 5/6/2005 02:34:42 PM, Kind = Utc
'  ToLocalTime:     5/6/2005 07:34:42 AM, Kind = Local
'  ToUniversalTime: 5/6/2005 02:34:42 PM, Kind = Utc
'
'Local: ........... 5/6/2005 02:34:42 PM, Kind = Local
'  ToLocalTime:     5/6/2005 02:34:42 PM, Kind = Local
'  ToUniversalTime: 5/6/2005 09:34:42 PM, Kind = Utc
'
'Unspecified: ..... 5/6/2005 02:34:42 PM, Kind = Unspecified
'  ToLocalTime:     5/6/2005 07:34:42 AM, Kind = Local
'  ToUniversalTime: 5/6/2005 09:34:42 PM, Kind = Utc
'


Windows Phone OS

Supported in: 8.1, 8.0, 7.1, 7.0

Windows Phone

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