Type.IsInstanceOfType(Object) 方法

定义

命名空间:

System

程序集:

System.Runtime.dll

Source:

Type.cs

确定指定的对象是否是当前 Type 的实例。

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

参数

o

Object

要与当前类型进行比较的对象。

返回

Boolean

如果满足下列任一条件，则为 true：当前 Type 位于由 o 表示的对象的继承层次结构中；当前 Type 是 o 实现的接口。 如果不属于其中任一种情况，o 为 null，或者当前 Type 为开放式泛型类型（即 ContainsGenericParameters 返回 true），则为 false。

示例

下面的示例演示 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.

注解

派生类可以重写此方法。

注意

构造类型不是其泛型类型定义的实例。 也就是说， MyGenericList<int> Visual Basic) MyGenericList(Of Integer) 中的 (不是 Visual Basic) 中 (MyGenericList(Of T)的实例MyGenericList<T>。