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DateTime.Kind Property

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Gets a value that indicates whether the time represented by this instance is based on local time, Coordinated Universal Time (UTC), or neither.

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

Syntax

'Declaration
Public ReadOnly Property Kind As DateTimeKind
public DateTimeKind Kind { get; }

Property Value

Type: System.DateTimeKind
One of the enumeration values. The default is Unspecified.

Remarks

You can explicitly set the Kind property of a new DateTime value to a particular DateTimeKind value by calling the SpecifyKind method.

The Kind property allows a DateTime value to clearly reflect either Coordinated Universal Time (UTC) or the local time. In contrast, the DateTimeOffset structure can unambiguously reflect any time in any time zone as a single point in time.

Examples

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

using System;

class Example
{
   public static void Demo(System.Windows.Controls.TextBlock outputBlock)
   {
      // Get the date and time for the current moment, adjusted 
      // to the local time zone.

      DateTime saveNow = DateTime.Now;

      // Get the date and time for the current moment expressed 
      // as coordinated universal time (UTC).

      DateTime saveUtcNow = DateTime.UtcNow;
      DateTime myDt;

      // 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 += "\n";

      // 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);
   }

   // 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 static string datePatt = @"M/d/yyyy hh:mm:ss tt";
   public static void Display(System.Windows.Controls.TextBlock outputBlock, string title, DateTime inputDt)
   {
      DateTime dispDt = inputDt;
      string dtString;

      // Display the original DateTime.

      dtString = dispDt.ToString(datePatt);
      outputBlock.Text += String.Format("{0} {1}, Kind = {2}",
                        title, dtString, dispDt.Kind) + "\n";

      // 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) + "\n";

      // 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) + "\n";
      outputBlock.Text += "\n";
   }

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

   public static void DisplayNow(System.Windows.Controls.TextBlock outputBlock, string title, DateTime inputDt)
   {
      string dtString = inputDt.ToString(datePatt);
      outputBlock.Text += String.Format("{0} {1}, Kind = {2}",
                        title, dtString, inputDt.Kind) + "\n";
   }
}

/*
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

*/

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.