GC.ReRegisterForFinalize(Object) メソッド

定義

SuppressFinalize(Object) が事前に呼び出されている指定オブジェクトに対して、ファイナライザーを呼び出すことをシステムに要求します。

public:
 static void ReRegisterForFinalize(System::Object ^ obj);
public static void ReRegisterForFinalize (object obj);
static member ReRegisterForFinalize : obj -> unit
Public Shared Sub ReRegisterForFinalize (obj As Object)

パラメーター

obj
Object

ファイナライザーの呼び出しが必要なオブジェクト。

例外

objnullです。

次の例では、 メソッドを使用 ReRegisterForFinalize して、ガベージ コレクション後に 2 回目にオブジェクトを最終処理する方法を示します。

using namespace System;
ref class MyFinalizeObject
{
public:
   static MyFinalizeObject^ currentInstance = nullptr;

private:
   bool hasFinalized;

public:
   MyFinalizeObject()
   {
      hasFinalized = false;
   }

   ~MyFinalizeObject()
   {
      if ( hasFinalized == false )
      {
         Console::WriteLine( "First finalization" );
         
         // Put this object back into a root by creating
         // a reference to it.
         MyFinalizeObject::currentInstance = this;
         
         // Indicate that this instance has finalized once.
         hasFinalized = true;
         
         // Place a reference to this object back in the
         // finalization queue.
         GC::ReRegisterForFinalize( this );
      }
      else
      {
         Console::WriteLine( "Second finalization" );
      }
   }

};

int main()
{
   
   // Create a MyFinalizeObject.
   MyFinalizeObject^ mfo = gcnew MyFinalizeObject;
   
   // Release the reference to mfo.
   mfo = nullptr;
   
   // Force a garbage collection.
   GC::Collect();
   
   // At this point mfo will have gone through the first Finalize.
   // There should now be a reference to mfo in the static
   // MyFinalizeObject::currentInstance field.  Setting this value
   // to 0 and forcing another garbage collection will now
   // cause the object to Finalize permanently.
   MyFinalizeObject::currentInstance = nullptr;
   GC::Collect();
}
using System;

namespace ReRegisterForFinalizeExample
{
    class MyMainClass
    {
        static void Main()
        {
            // Create a MyFinalizeObject.
            MyFinalizeObject mfo = new MyFinalizeObject();

            // Release the reference to mfo.
            mfo = null;

            // Force a garbage collection.
            GC.Collect();

            // At this point mfo will have gone through the first Finalize.
            // There should now be a reference to mfo in the static
            // MyFinalizeObject.currentInstance field.  Setting this value
            // to null and forcing another garbage collection will now
            // cause the object to Finalize permanently.
            MyFinalizeObject.currentInstance = null;
            GC.Collect();
        }
    }

    class MyFinalizeObject
    {
        public static MyFinalizeObject currentInstance = null;
        private bool hasFinalized = false;

        ~MyFinalizeObject()
        {
            if(hasFinalized == false)
            {
                Console.WriteLine("First finalization");

                // Put this object back into a root by creating
                // a reference to it.
                MyFinalizeObject.currentInstance = this;

                // Indicate that this instance has finalized once.
                hasFinalized = true;

                // Place a reference to this object back in the
                // finalization queue.
                GC.ReRegisterForFinalize(this);
            }
            else
            {
                Console.WriteLine("Second finalization");
            }
        }
    }
}
open System

[<AllowNullLiteral>]
type MyFinalizeObject() =
    let mutable hasFinalized = false
    
    static member val CurrentInstance = null with get, set

    override this.Finalize() =
        if hasFinalized then
            printfn "First finalization"

            // Put this object back into a root by creating a reference to it.
            MyFinalizeObject.CurrentInstance <- this

            // Indicate that this instance has finalized once.
            hasFinalized <- true

            // Place a reference to this object back in the finalization queue.
            GC.ReRegisterForFinalize this
        else 
            printfn "Second finalization"

// Create a MyFinalizeObject.
let mutable mfo = MyFinalizeObject()

// Release the reference to mfo.
mfo <- null

// Force a garbage collection.
GC.Collect()

// At this point mfo will have gone through the first Finalize.
// There should now be a reference to mfo in the static
// MyFinalizeObject.CurrentInstance property. Setting this value
// to null and forcing another garbage collection will now
// cause the object to Finalize permanently.
MyFinalizeObject.CurrentInstance <- null
GC.Collect()
Namespace ReRegisterForFinalizeExample
    Class MyMainClass
        Shared Sub Main()
            'Create a MyFinalizeObject.
            Dim mfo As New MyFinalizeObject()

            'Release the reference to mfo.
            mfo = Nothing

            'Force a garbage collection.
            GC.Collect()

            'At this point mfo will have gone through the first Finalize.
            'There should now be a reference to mfo in the static
            'MyFinalizeObject.currentInstance field.  Setting this value
            'to null and forcing another garbage collection will now
            'cause the object to Finalize permanently.
            MyFinalizeObject.currentInstance = Nothing
            GC.Collect()
        End Sub
    End Class

    Class MyFinalizeObject
        Public Shared currentInstance As MyFinalizeObject = Nothing
        Private hasFinalized As Boolean = False

        Protected Overrides Sub Finalize()
            If hasFinalized = False Then
                Console.WriteLine("First finalization")

                'Put this object back into a root by creating
                'a reference to it.
                MyFinalizeObject.currentInstance = Me

                'Indicate that this instance has finalized once.
                hasFinalized = True

                'Place a reference to this object back in the
                'finalization queue.
                GC.ReRegisterForFinalize(Me)
            Else
                Console.WriteLine("Second finalization")
            End If
            MyBase.Finalize()
        End Sub
    End Class
End Namespace

注釈

メソッドは ReRegisterForFinalize 、ガベージ コレクターが obj オブジェクトを解放する前に、ファイナライズを要求するオブジェクトの一覧に パラメーターを追加します。 パラメーターは obj 、このメソッドの呼び出し元である必要があります。

メソッドを ReRegisterForFinalize 呼び出しても、ガベージ コレクターがオブジェクトのファイナライザーを呼び出すことは保証されません。

既定では、ファイナライザーを実装するすべてのオブジェクトが、ファイナライズを必要とするオブジェクトの一覧に追加されます。ただし、オブジェクトが既にファイナライズされているか、 メソッドを呼び出してファイナライズを SuppressFinalize 無効にしている可能性があります。

ファイナライザーは、このメソッドを使用して、自身または参照するオブジェクトを再取得できます。

適用対象

こちらもご覧ください