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DateTime.Now Property

Updated: August 2010

Gets a DateTime object that is set to the current date and time on this computer, expressed as the local time.

Namespace:  System
Assembly:  mscorlib (in mscorlib.dll)
public static DateTime Now { get; }

Property Value

Type: System.DateTime
A DateTime whose value is the current local date and time.

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 Now property is frequently used to measure performance. However, because of its low resolution, it is not suitable for use as a benchmarking tool. A better alternative is to use the Stopwatch class.

Starting with the .NET Framework version 2.0, the return value is a DateTime whose Kind property returns DateTimeKind.Local.

NoteNote:

You can also use the Now property to retrieve the current local date and time. It allows a local time to be expressed unambiguously as a single point in time, which in turn makes that time value portable across computers.

Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows CE Platform Note: In Windows CE, time is specific only to the second. You can get a more precise time span measurement, for example, in milliseconds, by using the TickCount property.

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. 

using System;

class Sample 
{
    public static void Main() 
    {
// 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("UtcNow: ..........", saveUtcNow);
    DisplayNow("Now: .............", saveNow);
    Console.WriteLine();

// Change the Kind property of the current moment to  
// DateTimeKind.Utc and display the result.

    myDt = DateTime.SpecifyKind(saveNow, DateTimeKind.Utc);
    Display("Utc: .............", myDt);

// Change the Kind property of the current moment to  
// DateTimeKind.Local and display the result.

    myDt = DateTime.SpecifyKind(saveNow, DateTimeKind.Local);
    Display("Local: ...........", myDt);

// Change the Kind property of the current moment to  
// DateTimeKind.Unspecified and display the result.

    myDt = DateTime.SpecifyKind(saveNow, DateTimeKind.Unspecified);
    Display("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(string title, DateTime inputDt)
    {
    DateTime dispDt = inputDt;
    string dtString;

// Display the original DateTime.

    dtString = dispDt.ToString(datePatt);
    Console.WriteLine("{0} {1}, Kind = {2}", 
                      title, dtString, dispDt.Kind);

// 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);
    Console.WriteLine("  ToLocalTime:     {0}, Kind = {1}", 
                      dtString, dispDt.Kind);

// 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);
    Console.WriteLine("  ToUniversalTime: {0}, Kind = {1}", 
                      dtString, dispDt.Kind);
    Console.WriteLine();
    }

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

    public static void DisplayNow(string title, DateTime inputDt)
    {
    string dtString = inputDt.ToString(datePatt);
    Console.WriteLine("{0} {1}, Kind = {2}", 
                      title, dtString, inputDt.Kind);
    }
}

/*
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 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC, Xbox 360, Zune

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 3.5, 2.0, 1.0

XNA Framework

Supported in: 3.0, 2.0, 1.0

Date

History

Reason

August 2010

Added a remark about measuring performance with the Stopwatch class.

Customer feedback.

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