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DateTime.UtcNow Property

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Gets a DateTime object that is set to the current date and time on this computer, expressed as the Coordinated Universal Time (UTC).

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

Syntax

'Declaration
Public Shared ReadOnly Property UtcNow As DateTime
public static DateTime UtcNow { get; }

Property Value

Type: System.DateTime
An object whose value is the current UTC date and time.

Remarks

The resolution of this property depends on the system timer.

System

Approximate resolution

Windows NT 3.5 and later

10 milliseconds

Windows 98

55 milliseconds

The return value is a DateTime whose Kind property returns DateTimeKind.Utc.

An alternative to using UtcNow is DateTimeOffset.UtcNow. While the former indicates that a date and time value is Coordinated Universal Time (UTC) by assigning DateTimeKind.Utc to its Kind property, the latter assigns the date and time value the UTC time's offset (equal to TimeSpan.Zero).

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.