Type.IsInstanceOfType(Object) 方法

定義

命名空間:

System

組件:

System.Runtime.dll

Source:

Type.cs

判斷指定的物件是否為目前 Type 的執行個體。

public:
 virtual bool IsInstanceOfType(System::Object ^ o);

public virtual bool IsInstanceOfType (object? o);

abstract member IsInstanceOfType : obj -> bool
override this.IsInstanceOfType : obj -> bool

Public Overridable Function IsInstanceOfType (o As Object) As Boolean

參數

o

Object

要與目前的類型比較的物件。

傳回

Boolean

如果在目前 Type 位於 o 所代表之物件的階層架構中，或者目前 Type 位於 o 支援的介面中，則為 true。 如果都不是這些情況，或者如果 o 為 null，又或者如果目前 Type 為開放式泛型類型 (亦即 ContainsGenericParameters 會傳回 true)，則為 false。

範例

下列範例示範 IsInstanceOfType 方法的用法。

using namespace System;

public interface class IExample{};

public ref class BaseClass: IExample{};

public ref class DerivedClass: BaseClass{};

void main()
{
   Type^ interfaceType = IExample::typeid;
   BaseClass^ base1 = gcnew BaseClass;
   Type^ base1Type = base1->GetType();
   BaseClass^ derived1 = gcnew DerivedClass;
   Type^ derived1Type = derived1->GetType();
   array<Int32>^ arr = gcnew array<Int32>(11);
   Type^ arrayType = Array::typeid;

   Console::WriteLine("Is Int32[] an instance of the Array class? {0}.",
                      arrayType->IsInstanceOfType( arr ) );
   Console::WriteLine("Is myclass an instance of BaseClass? {0}.",
                      base1Type->IsInstanceOfType( base1 ) );
   Console::WriteLine("Is myderivedclass an instance of BaseClass? {0}.",
                      base1Type->IsInstanceOfType( derived1 ) );
   Console::WriteLine("Is myclass an instance of IExample? {0}.",
                      interfaceType->IsInstanceOfType( base1 ) );
   Console::WriteLine("Is myderivedclass an instance of IExample? {0}.",
                      interfaceType->IsInstanceOfType( derived1 ) );
}
// The example displays the following output:
//    Is int[] an instance of the Array class? True.
//    Is base1 an instance of BaseClass? True.
//    Is derived1 an instance of BaseClass? True.
//    Is base1 an instance of IExample? True.
//    Is derived1 an instance of IExample? True.

using System;

public interface IExample {}

public class BaseClass : IExample {}

public class DerivedClass : BaseClass {}

public class Example
{
    public static void Main()
    {
        var interfaceType = typeof(IExample);
        var base1 = new BaseClass();
        var base1Type = base1.GetType();
        var derived1 = new DerivedClass();
        var derived1Type = derived1.GetType();
        int[] arr = new int[11];

        Console.WriteLine("Is int[] an instance of the Array class? {0}.",
                           typeof(Array).IsInstanceOfType(arr));
        Console.WriteLine("Is base1 an instance of BaseClass? {0}.",
                          base1Type.IsInstanceOfType(base1));
        Console.WriteLine("Is derived1 an instance of BaseClass? {0}.",
                          base1Type.IsInstanceOfType(derived1));
        Console.WriteLine("Is base1 an instance of IExample? {0}.",
                          interfaceType.IsInstanceOfType(base1));
        Console.WriteLine("Is derived1 an instance of IExample? {0}.",
                          interfaceType.IsInstanceOfType(derived1));
    }
}
// The example displays the following output:
//    Is int[] an instance of the Array class? True.
//    Is base1 an instance of BaseClass? True.
//    Is derived1 an instance of BaseClass? True.
//    Is base1 an instance of IExample? True.
//    Is derived1 an instance of IExample? True.

open System

type IExample = interface end

type BaseClass() = interface IExample

type DerivedClass() = inherit BaseClass()

let interfaceType = typeof<IExample>
let base1 = BaseClass()
let base1Type = base1.GetType()
let derived1 = DerivedClass()
let derived1Type = derived1.GetType()
let arr = Array.zeroCreate<int> 11

printfn $"Is int[] an instance of the Array class? {typeof<Array>.IsInstanceOfType arr}."
printfn $"Is base1 an instance of BaseClass? {base1Type.IsInstanceOfType base1}."
printfn $"Is derived1 an instance of BaseClass? {base1Type.IsInstanceOfType derived1}."
printfn $"Is base1 an instance of IExample? {interfaceType.IsInstanceOfType base1}."
printfn $"Is derived1 an instance of IExample? {interfaceType.IsInstanceOfType derived1}."
// The example displays the following output:
//    Is int[] an instance of the Array class? True.
//    Is base1 an instance of BaseClass? True.
//    Is derived1 an instance of BaseClass? True.
//    Is base1 an instance of IExample? True.
//    Is derived1 an instance of IExample? True.

Public Interface IExample
End Interface

Public Class BaseClass : Implements IExample
End Class

Public Class DerivedClass : Inherits BaseClass
End Class

Public Module Example
    Public Sub Main()
        Dim interfaceType As Type = GetType(IExample)
        Dim base1 As New BaseClass()
        Dim base1Type As Type = base1.GetType()
        Dim derived1 = New DerivedClass()
        Dim derived1Type As Type = derived1.GetType()
        Dim arr(10) As Integer

        Console.WriteLine("Is int[] an instance of the Array class? {0}.",
                           GetType(Array).IsInstanceOfType(arr))
        Console.WriteLine("Is base1 an instance of BaseClass? {0}.",
                          base1Type.IsInstanceOfType(base1))
        Console.WriteLine("Is derived1 an instance of BaseClass? {0}.",
                          base1Type.IsInstanceOfType(derived1))
        Console.WriteLine("Is base1 an instance of IExample? {0}.",
                          interfaceType.IsInstanceOfType(base1))
        Console.WriteLine("Is derived1 an instance of IExample? {0}.",
                          interfaceType.IsInstanceOfType(derived1))
    End Sub
End Module
' The example displays the following output:
'    Is int[] an instance of the Array class? True.
'    Is base1 an instance of BaseClass? True.
'    Is derived1 an instance of BaseClass? True.
'    Is base1 an instance of IExample? True.
'    Is derived1 an instance of IExample? True.

備註

這個方法可由衍生類別覆寫。

注意

建構的類型不是其泛型型別定義的實例。 也就是說， MyGenericList<int> Visual Basic) 中的 (MyGenericList(Of Integer) 不是 Visual Basic) 中 (MyGenericList(Of T) 的實例 MyGenericList<T> 。