Object.GetType Object.GetType Object.GetType Object.GetType Method

Définition

Obtient le Type de l'instance actuelle.Gets the Type of the current instance.

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

Retours

Type exact de l'instance actuelle au moment de l'exécution.The exact runtime type of the current instance.

Exemples

L’exemple de code suivant montre que GetType retourne le type de runtime de l’instance actuelle.The following code example demonstrates that GetType returns the runtime type of the current instance.

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

Remarques

Étant donné que System.Object est la classe de base pour tous les types dans le système de type .NET Framework, le GetType méthode peut être utilisée pour retourner Type objets qui représentent tous les types .NET Framework.Because System.Object is the base class for all types in the .NET Framework type system, the GetType method can be used to return Type objects that represent all .NET Framework types. Le .NET Framework reconnaît les cinq catégories de types suivantes :The .NET Framework recognizes the following five categories of types:

Pour les deux objets x et y qui comportent des types de runtime identiques, Object.ReferenceEquals(x.GetType(),y.GetType()) retourne true.For two objects x and y that have identical runtime types, Object.ReferenceEquals(x.GetType(),y.GetType()) returns true. L’exemple suivant utilise le GetType méthode avec le ReferenceEquals méthode pour déterminer si une valeur numérique est du même type que deux autres valeurs numériques.The following example uses the GetType method with the ReferenceEquals method to determine whether one numeric value is the same type as two other numeric values.

using System;

public class Example
{
   public static void Main()
   {
      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      

Notes

Pour déterminer si un objet est un type spécifique, vous pouvez utiliser le mot clé de comparaison du type de votre langage ou construire.To determine whether an object is a specific type, you can use your language's type comparison keyword or construct. Par exemple, vous pouvez utiliser la TypeOf…Is construire en Visual Basic ou le is mot clé en c#.For example, you can use the TypeOf…Is construct in Visual Basic or the is keyword in C#.

Le GetType méthode est héritée par tous les types qui dérivent de Object.The GetType method is inherited by all types that derive from Object. Cela signifie que, outre à l’aide du mot clé de comparaison de votre propre langage, vous pouvez utiliser la GetType méthode pour déterminer le type d’un objet particulier, comme le montre l’exemple suivant.This means that, in addition to using your own language's comparison keyword, you can use the GetType method to determine the type of a particular object, as the following example shows.

using System;

public class Example
{
   public static void Main()
   {
      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 32-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 32-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.

Le Type objet expose les métadonnées associées à la classe de l’actuel Object.The Type object exposes the metadata associated with the class of the current Object.

S’applique à

Voir aussi