Object.GetType Methode

Definition

Ruft den Type der aktuellen Instanz ab.

public:
 Type ^ GetType();
public Type GetType ();
member this.GetType : unit -> Type
Public Function GetType () As Type

Gibt zurück

Type

Der genaue Laufzeittyp der aktuellen Instanz.

Beispiele

Im folgenden Codebeispiel wird veranschaulicht, dass GetType den Laufzeittyp der aktuellen Instanz zurückgibt.

using namespace System;

public ref class MyBaseClass {};

public ref class MyDerivedClass: MyBaseClass{};

int main()
{
   MyBaseClass^ myBase = gcnew MyBaseClass;
   MyDerivedClass^ myDerived = gcnew MyDerivedClass;
   Object^ o = myDerived;
   MyBaseClass^ b = myDerived;
   Console::WriteLine( "mybase: Type is {0}", myBase->GetType() );
   Console::WriteLine( "myDerived: Type is {0}", myDerived->GetType() );
   Console::WriteLine( "object o = myDerived: Type is {0}", o->GetType() );
   Console::WriteLine( "MyBaseClass b = myDerived: Type is {0}", b->GetType() );
}

/*

This code produces the following output.

mybase: Type is MyBaseClass
myDerived: Type is MyDerivedClass
object o = myDerived: Type is MyDerivedClass
MyBaseClass b = myDerived: Type is MyDerivedClass 

*/
using System;

public class MyBaseClass {
}

public class MyDerivedClass: MyBaseClass {
}

public class Test
{
   public static void Main()
   {
      MyBaseClass myBase = new MyBaseClass();
      MyDerivedClass myDerived = new MyDerivedClass();
      object o = myDerived;
      MyBaseClass b = myDerived;

      Console.WriteLine("mybase: Type is {0}", myBase.GetType());
      Console.WriteLine("myDerived: Type is {0}", myDerived.GetType());
      Console.WriteLine("object o = myDerived: Type is {0}", o.GetType());
      Console.WriteLine("MyBaseClass b = myDerived: Type is {0}", b.GetType());
   }
}
// The example displays the following output:
//    mybase: Type is MyBaseClass
//    myDerived: Type is MyDerivedClass
//    object o = myDerived: Type is MyDerivedClass
//    MyBaseClass b = myDerived: Type is MyDerivedClass
' Define a base and a derived class.
Public Class MyBaseClass
End Class 

Public Class MyDerivedClass : Inherits MyBaseClass
End Class 

Public Class Test
    Public Shared Sub Main() 
        Dim base As New MyBaseClass()
        Dim derived As New MyDerivedClass()
        Dim o As Object = derived
        Dim b As MyBaseClass = derived
        
        Console.WriteLine("base.GetType returns {0}", base.GetType())
        Console.WriteLine("derived.GetType returns {0}", derived.GetType())
        Console.WriteLine("Dim o As Object = derived; o.GetType returns {0}", o.GetType())
        Console.WriteLine("Dim b As MyBaseClass = derived; b.Type returns {0}", b.GetType())
    End Sub 
End Class 
' The example displays the following output:
'    base.GetType returns MyBaseClass
'    derived.GetType returns MyDerivedClass
'    Dim o As Object = derived; o.GetType returns MyDerivedClass
'    Dim b As MyBaseClass = derived; b.Type returns MyDerivedClass

Hinweise

Da System.Object die Basisklasse für alle Typen im .NET-Typsystem ist, kann die GetType -Methode verwendet werden, um Type Objekte zurückzugeben, die alle .NET-Typen darstellen. .NET erkennt die folgenden fünf Kategorien von Typen:

Gibt für zwei Objekte x und y , die identische Laufzeittypen haben, Object.ReferenceEquals(x.GetType(),y.GetType()) true zurück. Im folgenden Beispiel wird die GetType -Methode mit der ReferenceEquals -Methode verwendet, um zu bestimmen, ob ein numerischer Wert vom gleichen Typ wie zwei andere numerische Werte ist.

int n1 = 12;
int n2 = 82;
long n3 = 12;

Console.WriteLine("n1 and n2 are the same type: {0}",
                  Object.ReferenceEquals(n1.GetType(), n2.GetType()));
Console.WriteLine("n1 and n3 are the same type: {0}",
                  Object.ReferenceEquals(n1.GetType(), n3.GetType()));

// The example displays the following output:
//       n1 and n2 are the same type: True
//       n1 and n3 are the same type: False
Module Example
   Public Sub Main()
      Dim n1 As Integer = 12
      Dim n2 As Integer = 82
      Dim n3 As Long = 12
      
      Console.WriteLine("n1 and n2 are the same type: {0}",
                        Object.ReferenceEquals(n1.GetType(), n2.GetType()))
      Console.WriteLine("n1 and n3 are the same type: {0}",
                        Object.ReferenceEquals(n1.GetType(), n3.GetType()))
   End Sub
End Module
' The example displays the following output:
'       n1 and n2 are the same type: True
'       n1 and n3 are the same type: False

Hinweis

Um zu bestimmen, ob ein Objekt ein bestimmter Typ ist, können Sie das Typvergleichsschlüsselwort oder -konstrukt Ihrer Sprache verwenden. Beispielsweise können Sie das TypeOf…Is -Konstrukt in Visual Basic oder das is Schlüsselwort in C# verwenden.

Die GetType -Methode wird von allen Typen geerbt, die von abgeleitet Object sind. Dies bedeutet, dass Sie zusätzlich zur Verwendung des Vergleichsschlüsselworts Ihrer eigenen Sprache auch die -Methode verwenden können, GetType um den Typ eines bestimmten Objekts zu bestimmen, wie im folgenden Beispiel gezeigt.

object[] values = { (int) 12, (long) 10653, (byte) 12, (sbyte) -5,
                   16.3, "string" };
foreach (var value in values) {
   Type t = value.GetType();
   if (t.Equals(typeof(byte)))
      Console.WriteLine("{0} is an unsigned byte.", value);
   else if (t.Equals(typeof(sbyte)))
      Console.WriteLine("{0} is a signed byte.", value);
   else if (t.Equals(typeof(int)))
      Console.WriteLine("{0} is a 32-bit integer.", value);
   else if (t.Equals(typeof(long)))
      Console.WriteLine("{0} is a 64-bit integer.", value);
   else if (t.Equals(typeof(double)))
      Console.WriteLine("{0} is a double-precision floating point.",
                        value);
   else
      Console.WriteLine("'{0}' is another data type.", value);
}

// The example displays the following output:
//    12 is a 32-bit integer.
//    10653 is a 32-bit integer.
//    12 is an unsigned byte.
//    -5 is a signed byte.
//    16.3 is a double-precision floating point.
//    'string' is another data type.
Module Example
   Public Sub Main()
      Dim values() As Object = { 12, CLng(10653), CByte(12), 
                                 CSbyte(-5), 16.3, "string" } 
      For Each value In values
         Dim t AS Type = value.GetType()
         If t.Equals(GetType(Byte))
            Console.WriteLine("{0} is an unsigned byte.", value)
         ElseIf t.Equals(GetType(SByte))
            Console.WriteLine("{0} is a signed byte.", value)
         ElseIf t.Equals(GetType(Integer))   
            Console.WriteLine("{0} is a 32-bit integer.", value)
         ElseIf t.Equals(GetType(Long))   
            Console.WriteLine("{0} is a 64-bit integer.", value)
         ElseIf t.Equals(GetType(Double))
            Console.WriteLine("{0} is a double-precision floating point.", 
                              value)
         Else
            Console.WriteLine("'{0}' is another data type.", value)
         End If   
      Next      
   End Sub
End Module
' The example displays the following output:
'       12 is a 32-bit integer.
'       10653 is a 32-bit integer.
'       12 is an unsigned byte.
'       -5 is a signed byte.
'       16.3 is a double-precision floating point.
'       'string' is another data type.

Das Type -Objekt macht die Metadaten verfügbar, die der -Klasse des aktuellen zugeordnet Object sind.

Gilt für

Siehe auch