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DateTime.ToUniversalTime-Methode

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Konvertiert den Wert des aktuellen DateTime-Objekts in koordinierte Weltzeit (UTC).

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

Syntax

'Declaration
Public Function ToUniversalTime As DateTime
'Usage
Dim instance As DateTime
Dim returnValue As DateTime

returnValue = instance.ToUniversalTime

public DateTime ToUniversalTime ()

public:
DateTime ToUniversalTime ()

public DateTime ToUniversalTime ()

public function ToUniversalTime () : DateTime

Rückgabewert

Ein DateTime-Objekt, dessen Kind-Eigenschaft Utc ist und dessen Wert die UTC-Zeit ist, die dem Wert des aktuellen DateTime-Objekts entspricht, oder MaxValue, wenn der konvertierte Wert zu groß ist, um von einem DateTime-Objekt dargestellt werden zu können, oder MinValue, wenn der konvertierte Wert zu klein ist, um von einem DateTime-Objekt dargestellt werden zu können.

Hinweise

Die UTC-Zeit ist gleich der Ortszeit minus UTC-Offset. Weitere Informationen über den UTC-Offset finden Sie unter TimeZone.GetUtcOffset. Bei der Konvertierung werden auch die Regeln für die Sommerzeit berücksichtigt, die für die durch das aktuelle DateTime-Objekt dargestellte Zeit gilt.

Ab .NET Framework, Version 2.0, wird der von der ToUniversalTime-Methode zurückgegebene Wert durch die Kind-Eigenschaft des aktuellen DateTime-Objekts bestimmt. In der folgenden Tabelle werden die möglichen Ergebnisse beschrieben:

Art

Ergebnisse

Utc

Es wird keine Konvertierung durchgeführt.

Local

Das aktuelle DateTime-Objekt wird in UTC konvertiert.

Unspecified

Beim aktuellen DateTime-Objekt wird davon ausgegangen, dass es sich um eine lokale Zeit handelt, und die Konvertierungen werden ausgeführt, als ob KindLocal ist.

Der von dieser Konvertierung zurückgegebene Wert ist ein DateTime-Objekt, dessen Kind-Eigenschaft Utc ist. Infolgedessen wird ein gültiges Ergebnis zurückgegeben, auch wenn ToUniversalTime wiederholt auf das gleiche DateTime-Objekt angewendet wird.

Diese Methode verwendet für Berechnungen immer die lokale Zeitzone.

Beispiel

Im folgenden Codebeispiel wird die ToUniversalTime-Methode veranschaulicht.

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); 

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 );

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 exp) {
    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 exp) {
    System.Console.WriteLine("Invalid format.");
    return;
}
localDateTime = univDateTime.ToLocalTime();
System.Console.WriteLine("{0} universal time is {1} local time.", 
    univDateTime, localDateTime);

Im folgenden Codebeispiel wird mithilfe der SpecifyKind-Methode veranschaulicht, wie sich die Kind-Eigenschaft auf die ToLocalTime-Konvertierungsmethode und die ToUniversalTime-Konvertierungsmethode auswirkt.

' 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

*/

Plattformen

Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile für Pocket PC, Windows Mobile für Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

.NET Framework unterstützt nicht alle Versionen sämtlicher Plattformen. Eine Liste der unterstützten Versionen finden Sie unter Systemanforderungen.

Versionsinformationen

.NET Framework

Unterstützt in: 2.0, 1.1, 1.0

.NET Compact Framework

Unterstützt in: 2.0, 1.0

Siehe auch

Referenz

DateTime-Struktur
DateTime-Member
System-Namespace
ToLocalTime