Object.GetType Methode
Definition
Wichtig
Einige Informationen beziehen sich auf Vorabversionen, die vor dem Release ggf. grundlegend überarbeitet werden. Microsoft übernimmt hinsichtlich der hier bereitgestellten Informationen keine Gewährleistungen, seien sie ausdrücklich oder konkludent.
Ruft die Type der aktuellen Instanz ab.
public:
Type ^ GetType();public Type GetType();member this.GetType : unit -> TypePublic Function GetType () As TypeGibt zurück
Der genaue Laufzeittyp der aktuellen Instanz.
Beispiele
Im folgenden Codebeispiel wird veranschaulicht, dass GetType der Laufzeittyp der aktuellen Instanz zurückgegeben wird.
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
type MyBaseClass() = class end
type MyDerivedClass() =
inherit MyBaseClass()
let myBase = MyBaseClass()
let myDerived = MyDerivedClass()
let o: obj = myDerived
let b: MyBaseClass = myDerived
printfn $"mybase: Type is {myBase.GetType()}"
printfn $"myDerived: Type is {myDerived.GetType()}"
printfn $"object o = myDerived: Type is {o.GetType()}"
printfn $"MyBaseClass b = myDerived: Type is {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 methode GetType verwendet werden, um Type-Objekte zurückzugeben, die alle .NET Typen darstellen. .NET erkennt die folgenden fünf Typenkategorien:
- Klassen, die von System.Object.
- Werttypen, die von System.ValueType.
- Schnittstellen, die von System.Object.
- Aufzählungen, die von System.Enum.
- Delegaten, die von System.MulticastDelegate.
Gibt für zwei Objekte x mit y identischen Laufzeittypen Object.ReferenceEquals(x.GetType(),y.GetType()) zurück true. Im folgenden Beispiel wird die Methode mit der GetTypeReferenceEquals Methode verwendet, um zu bestimmen, ob ein numerischer Wert derselbe Typ ist wie zwei andere numerische Werte.
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
open System
let n1 = 12
let n2 = 82
let n3 = 12L
printfn $"n1 and n2 are the same type: {Object.ReferenceEquals(n1.GetType(), n2.GetType())}"
printfn $"n1 and n3 are the same type: {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
Note
Um zu ermitteln, ob ein Objekt ein bestimmter Typ ist, können Sie das Schlüsselwort für den Typvergleich ihrer Sprache oder das Konstrukt verwenden. Sie können z. B. das TypeOf…Is-Konstrukt in Visual Basic oder das Schlüsselwort is in C# verwenden.
Die GetType Methode wird von allen Typen geerbt, die von Object. Dies bedeutet, dass Sie neben dem Vergleichsschlüsselwort Ihrer eigenen Sprache auch die GetType Methode verwenden können, 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 64-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.
let values: obj[] =
[| 12; 10653L; 12uy
-5y; 16.3; "string" |]
for value in values do
let t = value.GetType()
if t.Equals typeof<byte> then
printfn $"{value} is an unsigned byte."
elif t.Equals typeof<sbyte> then
printfn $"{value} is a signed byte."
elif t.Equals typeof<int> then
printfn $"{value} is a 32-bit integer."
elif t.Equals typeof<int64> then
printfn $"{value} is a 64-bit integer."
elif t.Equals typeof<double> then
printfn $"{value} is a double-precision floating point."
else
printfn $"'{value}' is another data type."
// 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 der aktuellen ObjectKlasse zugeordnet sind.