DateTime.ToUniversalTime (Método) (System)

ToUniversalTime (Método)

Contraer todo

Filtro de lenguage

Ver contenido: en paralelo

.NET Framework Class Library

DateTime..::.ToUniversalTime Method

Converts the value of the current DateTime object to Coordinated Universal Time (UTC).

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

Syntax

Visual Basic

Public Function ToUniversalTime As DateTime

public DateTime ToUniversalTime()

Visual C++

public:
DateTime ToUniversalTime()

member ToUniversalTime : unit -> DateTime

Return Value

Type: System..::.DateTime
An object whose Kind property is Utc, and whose value is the UTC equivalent to the value of the current DateTime object, or MaxValue if the converted value is too large to be represented by a DateTime object, or MinValue if the converted value is too small to be represented by a DateTime object.

Remarks

The Coordinated Universal Time (UTC) is equal to the local time minus the UTC offset. For more information about the UTC offset, see TimeZone..::.GetUtcOffset. The conversion also takes into account the daylight saving time rule that applies to the time represented by the current DateTime object.

Important
On Windows XP systems, the ToUniversalTime method recognizes only the current adjustment rule when converting from local time to UTC. As a result, conversions for periods before the current adjustment rule came into effect may not accurately reflect the difference between local time and UTC.

Starting with the .NET Framework version 2.0, the value returned by the ToUniversalTime method is determined by the Kind property of the current DateTime object. The following table describes the possible results.

Kind	Results
Utc	No conversion is performed.
Local	The current DateTime object is converted to UTC.
Unspecified	The current DateTime object is assumed to be a local time, and the conversion is performed as if Kind were Local.

Note
The ToUniversalTime method converts a DateTime value from local time to UTC. To convert the time in a non-local time zone to UTC, use the TimeZoneInfo..::.ConvertTimeToUtc(DateTime, TimeZoneInfo) method. To convert a time whose offset from UTC is known, use the ToUniversalTime method.

If the date and time instance value is an ambiguous time, this method assumes that it is a standard time. (An ambiguous time is one that can map either to a standard time or to a daylight saving time in the local time zone) If the date and time instance value is an invalid time, this method simply subtracts the local time from the local time zone's UTC offset to return UTC. (An invalid time is one that does not exist because of the application of daylight saving time adjustment rules.)

Notes to Callers

The ToUniversalTime method is sometimes used to convert a local time to UTC. The ToLocalTime method is then called to restore the original local time. However, if the original time represents an invalid time in the local time zone, the two local time values will not be equal. For additional information and an example, see the ToLocalTime method.

On Windows XP systems, the ToUniversalTime method recognizes only the current adjustment rule for the local time zone, which it applies to all dates, including down-level dates (that is, dates that are earlier than the starting date of the current adjustment rule). Applications running on Windows XP that require historically accurate local date and time calculations must work around this behavior by using the FindSystemTimeZoneById method to retrieve a TimeZoneInfo object that corresponds to the local time zone and calling its TimeZoneInfo..::.ConvertTimeToUtc(DateTime, TimeZoneInfo) method.

The following example illustrates the difference between the ToUniversalTime and TimeZoneInfo..::.ConvertTimeToUtc(DateTime, TimeZoneInfo) methods on a Windows XP system in the U.S. Pacific Time zone. The first two method calls apply the current time zone adjustment rule (which went into effect in 2007) to a date in 2006. The current adjustment rule provides for the transition to daylight saving time on the second Sunday of March; the previous rule, which was in effect in 2006, provided for the transition to daylight saving time to occur on the first Sunday of April. Only the third method call accurately performs this historical date and time conversion.

Visual Basic

Module Example
   Public Sub Main()
      Dim date1 As Date = #3/21/2006 2:00AM#

      Console.WriteLine(date1.ToUniversalTime())
      Console.WriteLine(TimeZoneInfo.ConvertTimeToUtc(date1))

      Dim tz As TimeZoneInfo = TimeZoneInfo.FindSystemTimeZoneById("Pacific Standard Time")  
      Console.WriteLine(TimeZoneInfo.ConvertTimeToUtc(date1, tz))     
   End Sub
End Module
' The example displays the following output on Windows XP systems:
'       3/21/2006 9:00:00 AM
'       3/21/2006 9:00:00 AM
'       3/21/2006 10:00:00 AM

using System;

public class Example
{
   public static void Main()
   {
      DateTime date1 = new DateTime(2006, 3, 21, 2, 0, 0);

      Console.WriteLine(date1.ToUniversalTime());
      Console.WriteLine(TimeZoneInfo.ConvertTimeToUtc(date1));

      TimeZoneInfo tz = TimeZoneInfo.FindSystemTimeZoneById("Pacific Standard Time");  
      Console.WriteLine(TimeZoneInfo.ConvertTimeToUtc(date1, tz));     
   }
}
// The example displays the following output on Windows XP systems:
//       3/21/2006 9:00:00 AM
//       3/21/2006 9:00:00 AM
//       3/21/2006 10:00:00 AM

Examples

The following example demonstrates the ToUniversalTime method.

Visual Basic

System.Console.WriteLine("Enter a date and time.")
Dim strDateTime As String
strDateTime = System.Console.ReadLine()

Dim localDateTime As System.DateTime
Try
   localDateTime = System.DateTime.Parse(strDateTime)
Catch exp As System.FormatException
   System.Console.WriteLine("Invalid format.")
End Try

Dim univDateTime As System.DateTime
univDateTime = localDateTime.ToUniversalTime()

System.Console.WriteLine("{0} local time is {1} universal time.", _
                           localDateTime, _
                           univDateTime)

System.Console.WriteLine("Enter a date and time in universal time.")
strDateTime = System.Console.ReadLine()

Try
   univDateTime = System.DateTime.Parse(strDateTime)
Catch exp As System.FormatException
   System.Console.WriteLine("Invalid format.")
End Try

localDateTime = univDateTime.ToLocalTime()

System.Console.WriteLine("{0} universal time is {1} local time.", _
                           univDateTime, _
                           localDateTime)

            System.Console.WriteLine("Enter a date and time.");
            string strDateTime = System.Console.ReadLine();

            System.DateTime localDateTime;
            try {
                localDateTime = System.DateTime.Parse(strDateTime);
            }
            catch (System.FormatException) {
                System.Console.WriteLine("Invalid format.");
                return;
            }

            System.DateTime univDateTime = localDateTime.ToUniversalTime();

            System.Console.WriteLine("{0} local time is {1} universal time.",
                                     localDateTime,
                                     univDateTime); 
            
            System.Console.WriteLine("Enter a date and time in universal time.");
            strDateTime = System.Console.ReadLine();

            try {
                univDateTime = System.DateTime.Parse(strDateTime);
            }
            catch (System.FormatException) {
                System.Console.WriteLine("Invalid format.");
                return;
            }

            localDateTime = univDateTime.ToLocalTime();

            System.Console.WriteLine("{0} universal time is {1} local time.",
                                     univDateTime,
                                     localDateTime);

Visual C++

System::Console::WriteLine( "Enter a date and time." );
String^ strDateTime = System::Console::ReadLine();

System::DateTime localDateTime;
try
{
   localDateTime = System::DateTime::Parse( strDateTime );
}
catch ( System::FormatException^ ) 
{
   System::Console::WriteLine( "Invalid format." );
   return;
}

System::DateTime univDateTime = localDateTime.ToUniversalTime();

System::Console::WriteLine( "{0} local time is {1} universal time.",
   localDateTime, univDateTime );

System::Console::WriteLine( "Enter a date and time in universal time." );
strDateTime = System::Console::ReadLine();

try
{
   univDateTime = System::DateTime::Parse( strDateTime );
}
catch ( System::FormatException^ ) 
{
   System::Console::WriteLine( "Invalid format." );
   return;
}

localDateTime = univDateTime.ToLocalTime();

System::Console::WriteLine( "{0} universal time is {1} local time.",
   univDateTime, localDateTime );

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

Visual Basic


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

Class Sample
    Public Shared Sub Main() 
        ' 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("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)
    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 title As String, ByVal inputDt As DateTime) 
        Dim dispDt As DateTime = inputDt
        Dim dtString As String

        ' 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()
    End Sub 'Display


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

    Public Shared Sub DisplayNow(ByVal title As String, ByVal inputDt As DateTime) 
        Dim dtString As String = inputDt.ToString(datePatt)
        Console.WriteLine("{0} {1}, Kind = {2}", title, dtString, inputDt.Kind)
    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 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

*/

Version Information

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Portable Class Library

Supported in: Portable Class Library

Platforms

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role not supported), Windows Server 2003 SP2

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

Reference

DateTime Structure

System Namespace

ToLocalTime

Biblioteca de clases de .NET Framework

DateTime..::.ToUniversalTime (Método)

Convierte el valor del objeto DateTime actual a la hora universal coordinada (UCT).

Espacio de nombres: System
Ensamblado: mscorlib (en mscorlib.dll)

Sintaxis

Visual Basic

Public Function ToUniversalTime As DateTime

public DateTime ToUniversalTime()

Visual C++

public:
DateTime ToUniversalTime()

member ToUniversalTime : unit -> DateTime

Valor devuelto

Tipo: System..::.DateTime
Objeto cuya propiedad Kind es Utc y cuyo valor es la hora UTC equivalente al valor del objeto DateTime actual, o MaxValue si el valor convertido es demasiado grande para representarlo mediante un objeto DateTime, o MinValue si el valor convertido es demasiado pequeño para representarlo mediante un objeto DateTime.

Comentarios

La hora universal coordinada (UTC) es igual a la hora local menos el desplazamiento de UTC. Para obtener más información sobre el desplazamiento relativo al horario UTC, vea TimeZone..::.GetUtcOffset. La conversión también tiene en cuenta las reglas del horario de verano que se aplican a la hora representada por el objeto DateTime actual.

Importante
En sistemas Windows XP, el método ToUniversalTime solo reconoce la regla de ajuste actual al convertir la hora local en UTC. Como consecuencia, puede que las conversiones para períodos anteriores a la entrada en vigor de la regla de ajuste actual no reflejen con precisión la diferencia entre hora local y hora UTC.

A partir de la versión 2.0 de .NET Framework, el valor devuelto por el método ToUniversalTime viene determinado por la propiedad Kind del objeto DateTime actual. En la siguiente tabla se describen los posibles resultados.

Kind	Resultados
Utc	No se lleva a cabo ninguna conversión.
Local	El objeto DateTime actual se convierte a hora UTC.
Unspecified	Se supone que el objeto DateTime actual es una hora local y la conversión se realiza como si Kind fuera Local.

Nota
El método ToUniversalTime convierte un valor de DateTime de hora local a hora UTC. Para convertir la hora de una zona horaria no local a hora UTC, se debe utilizar el método TimeZoneInfo..::.ConvertTimeToUtc(DateTime, TimeZoneInfo). Para convertir una hora cuyo desplazamiento de UTC se conoce, se debe utilizar el método ToUniversalTime.

Si el valor de la instancia de fecha y hora es una hora ambigua, este método supone que se trata de una hora estándar. (Se dice que una hora es ambigua cuando se puede asignar a una hora estándar o a una hora correspondiente al horario de verano en la zona horaria local). Si el valor de la instancia de fecha y hora corresponde a una hora no válida, este método resta la hora local del desplazamiento de UTC de la zona horaria para devolver la hora UTC. Se dice que una hora no es válida cuando no existe debido a la aplicación de las reglas de ajuste del horario de verano.

Notas para los llamadores

El método ToUniversalTime se utiliza a veces para convertir una hora local en hora UTC. Entonces se llama al método ToLocalTime para restaurar la hora local original. Sin embargo, si el tiempo original representa una hora no válida en la zona horaria local, los dos valores de la hora local no serán iguales. Para obtener información adicional y un ejemplo, vea el método ToLocalTime.

En sistemas Windows XP, el método ToUniversalTime solo reconoce la regla de ajuste actual para la zona horaria local, que aplica a todas las fechas, incluidas las fechas de nivel inferior (es decir, fechas que son anteriores a la fecha de inicio de la regla de ajuste). Las aplicaciones que se ejecutan en Windows XP que requieren cálculos de fecha y hora locales históricamente precisos deben evitar este comportamiento utilizando el método FindSystemTimeZoneById para recuperar un objeto TimeZoneInfo que corresponde a la zona horaria local y llamando a su método TimeZoneInfo..::.ConvertTimeToUtc(DateTime, TimeZoneInfo).

En el siguiente ejemplo se muestra la diferencia entre los métodos ToUniversalTime y TimeZoneInfo..::.ConvertTimeToUtc(DateTime, TimeZoneInfo) en un sistema Windows XP en EE.UU. Las primeras dos llamadas al método aplican la regla de ajuste de zona horaria actual (que entró en efecto en 2007) a una fecha de 2006. La regla de ajuste actual incluye la transición al horario de verano en el segundo domingo de marzo; la regla anterior, que estaba en vigor en 2006, incluía la transición al horario de verano en el primer domingo de abril. Solo la tercera llamada al método realiza esta conversión de fecha y hora histórica con precisión.

Visual Basic

Module Example
   Public Sub Main()
      Dim date1 As Date = #3/21/2006 2:00AM#

      Console.WriteLine(date1.ToUniversalTime())
      Console.WriteLine(TimeZoneInfo.ConvertTimeToUtc(date1))

      Dim tz As TimeZoneInfo = TimeZoneInfo.FindSystemTimeZoneById("Pacific Standard Time")  
      Console.WriteLine(TimeZoneInfo.ConvertTimeToUtc(date1, tz))     
   End Sub
End Module
' The example displays the following output on Windows XP systems:
'       3/21/2006 9:00:00 AM
'       3/21/2006 9:00:00 AM
'       3/21/2006 10:00:00 AM

using System;

public class Example
{
   public static void Main()
   {
      DateTime date1 = new DateTime(2006, 3, 21, 2, 0, 0);

      Console.WriteLine(date1.ToUniversalTime());
      Console.WriteLine(TimeZoneInfo.ConvertTimeToUtc(date1));

      TimeZoneInfo tz = TimeZoneInfo.FindSystemTimeZoneById("Pacific Standard Time");  
      Console.WriteLine(TimeZoneInfo.ConvertTimeToUtc(date1, tz));     
   }
}
// The example displays the following output on Windows XP systems:
//       3/21/2006 9:00:00 AM
//       3/21/2006 9:00:00 AM
//       3/21/2006 10:00:00 AM

Ejemplos

En el siguiente ejemplo se muestra el método ToUniversalTime.

Visual Basic

System.Console.WriteLine("Enter a date and time.")
Dim strDateTime As String
strDateTime = System.Console.ReadLine()

Dim localDateTime As System.DateTime
Try
   localDateTime = System.DateTime.Parse(strDateTime)
Catch exp As System.FormatException
   System.Console.WriteLine("Invalid format.")
End Try

Dim univDateTime As System.DateTime
univDateTime = localDateTime.ToUniversalTime()

System.Console.WriteLine("{0} local time is {1} universal time.", _
                           localDateTime, _
                           univDateTime)

System.Console.WriteLine("Enter a date and time in universal time.")
strDateTime = System.Console.ReadLine()

Try
   univDateTime = System.DateTime.Parse(strDateTime)
Catch exp As System.FormatException
   System.Console.WriteLine("Invalid format.")
End Try

localDateTime = univDateTime.ToLocalTime()

System.Console.WriteLine("{0} universal time is {1} local time.", _
                           univDateTime, _
                           localDateTime)

            System.Console.WriteLine("Enter a date and time.");
            string strDateTime = System.Console.ReadLine();

            System.DateTime localDateTime;
            try {
                localDateTime = System.DateTime.Parse(strDateTime);
            }
            catch (System.FormatException) {
                System.Console.WriteLine("Invalid format.");
                return;
            }

            System.DateTime univDateTime = localDateTime.ToUniversalTime();

            System.Console.WriteLine("{0} local time is {1} universal time.",
                                     localDateTime,
                                     univDateTime); 
            
            System.Console.WriteLine("Enter a date and time in universal time.");
            strDateTime = System.Console.ReadLine();

            try {
                univDateTime = System.DateTime.Parse(strDateTime);
            }
            catch (System.FormatException) {
                System.Console.WriteLine("Invalid format.");
                return;
            }

            localDateTime = univDateTime.ToLocalTime();

            System.Console.WriteLine("{0} universal time is {1} local time.",
                                     univDateTime,
                                     localDateTime);

Visual C++

System::Console::WriteLine( "Enter a date and time." );
String^ strDateTime = System::Console::ReadLine();

System::DateTime localDateTime;
try
{
   localDateTime = System::DateTime::Parse( strDateTime );
}
catch ( System::FormatException^ ) 
{
   System::Console::WriteLine( "Invalid format." );
   return;
}

System::DateTime univDateTime = localDateTime.ToUniversalTime();

System::Console::WriteLine( "{0} local time is {1} universal time.",
   localDateTime, univDateTime );

System::Console::WriteLine( "Enter a date and time in universal time." );
strDateTime = System::Console::ReadLine();

try
{
   univDateTime = System::DateTime::Parse( strDateTime );
}
catch ( System::FormatException^ ) 
{
   System::Console::WriteLine( "Invalid format." );
   return;
}

localDateTime = univDateTime.ToLocalTime();

System::Console::WriteLine( "{0} universal time is {1} local time.",
   univDateTime, localDateTime );

En el siguiente ejemplo se utiliza el método SpecifyKind para mostrar cómo la propiedad Kind influye en los métodos de conversión ToLocalTime y ToUniversalTime.

Visual Basic


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

Class Sample
    Public Shared Sub Main() 
        ' 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("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)
    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 title As String, ByVal inputDt As DateTime) 
        Dim dispDt As DateTime = inputDt
        Dim dtString As String

        ' 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()
    End Sub 'Display


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

    Public Shared Sub DisplayNow(ByVal title As String, ByVal inputDt As DateTime) 
        Dim dtString As String = inputDt.ToString(datePatt)
        Console.WriteLine("{0} {1}, Kind = {2}", title, dtString, inputDt.Kind)
    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 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

*/

Información de versión

.NET Framework

Compatible con: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Compatible con: 4, 3.5 SP1

Compatible con:

Plataformas

Windows 7, Windows Vista SP1 o posterior, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (no se admite Server Core), Windows Server 2008 R2 (se admite Server Core con SP1 o posterior), Windows Server 2003 SP2

.NET Framework no admite todas las versiones de todas las plataformas. Para obtener una lista de las versiones compatibles, vea Requisitos de sistema de .NET Framework.

Vea también

Referencia

DateTime Estructura

System (Espacio de nombres)

ToLocalTime

Etiquetas

: Agregar una etiqueta

Contenido de la comunidad

Agregar contenido nuevo

Anotaciones

Administre su perfil | MSDN Flash en Español | Contacto | Aviso legal