Type.IsContextfulImpl Método
Importante
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Implementa a propriedade IsContextful e determina se o Type pode ser hospedado em um contexto.
protected:
virtual bool IsContextfulImpl();C#
protected virtual bool IsContextfulImpl ();abstract member IsContextfulImpl : unit -> bool
override this.IsContextfulImpl : unit -> boolProtected Overridable Function IsContextfulImpl () As Booleantrue se o Type puder ser hospedado em um contexto; caso contrário, false.
O exemplo a seguir demonstra um uso do IsContextfulImpl método.
using namespace System;
using namespace System::Reflection;
public ref class MyTypeDelegatorClass: public TypeDelegator
{
public:
String^ myElementType;
private:
Type^ myType;
public:
MyTypeDelegatorClass( Type^ myType )
: TypeDelegator( myType )
{
this->myType = myType;
}
protected:
// Override IsContextfulImpl.
virtual bool IsContextfulImpl() override
{
// Check whether the type is contextful.
if ( myType->IsContextful )
{
myElementType = " is contextful ";
return true;
}
return false;
}
};
public ref class MyTypeDemoClass{};
// This class demonstrates IsContextfulImpl.
public ref class MyContextBoundClass: public ContextBoundObject
{
public:
String^ myString;
};
int main()
{
try
{
MyTypeDelegatorClass^ myType;
Console::WriteLine( "Check whether MyContextBoundClass can be hosted in a context." );
// Check whether MyContextBoundClass is contextful.
myType = gcnew MyTypeDelegatorClass( MyContextBoundClass::typeid );
if ( myType->IsContextful )
{
Console::WriteLine( "{0} can be hosted in a context.", MyContextBoundClass::typeid );
}
else
{
Console::WriteLine( "{0} cannot be hosted in a context.", MyContextBoundClass::typeid );
}
myType = gcnew MyTypeDelegatorClass( MyTypeDemoClass::typeid );
Console::WriteLine( "\nCheck whether MyTypeDemoClass can be hosted in a context." );
if ( myType->IsContextful )
{
Console::WriteLine( "{0} can be hosted in a context.", MyTypeDemoClass::typeid );
}
else
{
Console::WriteLine( "{0} cannot be hosted in a context.", MyTypeDemoClass::typeid );
}
}
catch ( Exception^ e )
{
Console::WriteLine( "Exception: {0}", e->Message );
}
}
C#
using System;
using System.Reflection;
public class MyTypeDelegatorClass : TypeDelegator
{
public string myElementType = null;
private Type myType = null ;
public MyTypeDelegatorClass(Type myType) : base(myType)
{
this.myType = myType;
}
// Override IsContextfulImpl.
protected override bool IsContextfulImpl()
{
// Check whether the type is contextful.
if(myType.IsContextful)
{
myElementType = " is contextful ";
return true;
}
return false;
}
}
public class MyTypeDemoClass
{
public static void Main()
{
try
{
MyTypeDelegatorClass myType;
Console.WriteLine ("Check whether MyContextBoundClass can be hosted in a context.");
// Check whether MyContextBoundClass is contextful.
myType = new MyTypeDelegatorClass(typeof(MyContextBoundClass));
if( myType.IsContextful)
{
Console.WriteLine(typeof(MyContextBoundClass) + " can be hosted in a context.");
}
else
{
Console.WriteLine(typeof(MyContextBoundClass) + " cannot be hosted in a context.");
}
// Check whether the int type is contextful.
myType = new MyTypeDelegatorClass(typeof(MyTypeDemoClass));
Console.WriteLine ("\nCheck whether MyTypeDemoClass can be hosted in a context.");
if( myType.IsContextful)
{
Console.WriteLine(typeof(MyTypeDemoClass) + " can be hosted in a context.");
}
else
{
Console.WriteLine(typeof(MyTypeDemoClass) + " cannot be hosted in a context.");
}
}
catch( Exception e )
{
Console.WriteLine("Exception: {0}", e.Message);
}
}
}
// This class demonstrates IsContextfulImpl.
public class MyContextBoundClass : ContextBoundObject
{
public string myString = "This class is used to demonstrate members of the Type class.";
}
Imports System.Reflection
Public Class MyTypeDelegatorClass
Inherits TypeDelegator
Public myElementType As String = Nothing
Private myType As Type = Nothing
Public Sub New(ByVal myType As Type)
MyBase.New(myType)
Me.myType = myType
End Sub
' Override IsContextfulImpl.
Protected Overrides Function IsContextfulImpl() As Boolean
' Check whether the type is contextful.
If myType.IsContextful Then
myElementType = " is contextful "
Return True
End If
Return False
End Function 'IsContextfulImpl
End Class
Public Class MyTypeDemoClass
Public Shared Sub Main()
Try
Dim myType As MyTypeDelegatorClass
Console.WriteLine("Check whether MyContextBoundClass can be hosted in a context.")
' Check whether MyContextBoundClass is contextful.
myType = New MyTypeDelegatorClass(GetType(MyContextBoundClass))
If myType.IsContextful Then
Console.WriteLine(GetType(MyContextBoundClass).ToString() + " can be hosted in a context.")
Else
Console.WriteLine(GetType(MyContextBoundClass).ToString() + " cannot be hosted in a context.")
End If
' Check whether the int type is contextful.
myType = New MyTypeDelegatorClass(GetType(MyTypeDemoClass))
Console.WriteLine(ControlChars.NewLine + "Check whether MyTypeDemoClass can be hosted in a context.")
If myType.IsContextful Then
Console.WriteLine(GetType(MyTypeDemoClass).ToString() + " can be hosted in a context.")
Else
Console.WriteLine(GetType(MyTypeDemoClass).ToString() + " cannot be hosted in a context.")
End If
Catch e As Exception
Console.WriteLine("Exception: {0}", e.Message.ToString())
End Try
End Sub
End Class
' This class demonstrates the IsContextfulImpl method.
Public Class MyContextBoundClass
Inherits ContextBoundObject
Public myString As String = "This class is used to demonstrate members of the Type class."
End Class
Este método pode ser substituído por uma classe derivada.
Um contexto intercepta chamadas para os membros da classe e impõe políticas que são aplicadas à classe, como sincronização.
| Produto | Versões |
|---|---|
| .NET | Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7 |
| .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 |
| .NET Standard | 2.0, 2.1 |