Type.IsSealed 属性
重要
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获取一个值，该值指示 Type 是否声明为密封的。
public:
property bool IsSealed { bool get(); };C#
public bool IsSealed { get; }member this.IsSealed : boolPublic ReadOnly Property IsSealed As Boolean如果 true 被声明为密封的，则为 Type；否则为 false。
以下示例创建类的 sealed 实例，检查 IsSealed 属性，并显示结果。
using namespace System;
// Declare MyTestClass as sealed.
ref class TestClass sealed{};
int main()
{
TestClass^ testClassInstance = gcnew TestClass;
// Get the type of testClassInstance.
Type^ type = testClassInstance->GetType();
// Get the IsSealed property of the myTestClassInstance.
bool sealed = type->IsSealed;
Console::WriteLine("{0} is sealed: {1}.", type->FullName, sealed);
}
// The example displays the following output:
// TestClass is sealed: True.
C#
using System;
public class Example
{
// Declare InnerClass as sealed.
sealed public class InnerClass
{
}
public static void Main()
{
InnerClass inner = new InnerClass();
// Get the type of InnerClass.
Type innerType = inner.GetType();
// Get the IsSealed property of innerClass.
bool isSealed = innerType.IsSealed;
Console.WriteLine("{0} is sealed: {1}.", innerType.FullName, isSealed);
}
}
// The example displays the following output:
// Example+InnerClass is sealed: True.
module Example
// Declare InnerClass as sealed.
[<Sealed>]
type InnerClass() = class end
let inner = InnerClass()
// Get the type of InnerClass.
let innerType = inner.GetType()
// Get the IsSealed property of innerClass.
let isSealed = innerType.IsSealed
printfn $"{innerType.FullName} is sealed: {isSealed}."
// The example displays the following output:
// Example+InnerClass is sealed: True.
Public Class Example
' Declare InnerClass as sealed.
Public NotInheritable Class InnerClass
End Class
Public Shared Sub Main()
Dim inner As New InnerClass()
' Get the type of InnerClass.
Dim innerType As Type = inner.GetType()
' Get the IsSealed property of InnerClass.
Dim sealed As Boolean = innerType.IsSealed
Console.WriteLine("{0} is sealed: {1}.", innerType.FullName, sealed)
End Sub
End Class
' The example displays the following output:
' Example+InnerClass is sealed: True.
如果当前 Type 表示泛型类型的类型参数，则此属性始终返回 true。
| 产品 | 版本 |
|---|---|
| .NET | Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9, 10 |
| .NET Framework | 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1 |
| .NET Standard | 2.0, 2.1 |
