GC.ReRegisterForFinalize(Object) Metod

Definition

Begär att systemet anropar finaliseraren för det angivna objektet som SuppressFinalize(Object) tidigare har anropats.

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)

Parametrar

obj
Object

Objektet som en finaliserare måste anropas för.

Undantag

obj är null.

Exempel

I följande exempel visas hur du använder ReRegisterForFinalize metoden för att slutföra ett objekt en andra gång efter skräpinsamlingen.

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)
            {
                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

Kommentarer

Metoden ReRegisterForFinalize lägger till parametern obj i listan över objekt som begär slutförande innan skräpinsamlaren frigör objektet. Parametern obj måste vara anroparen för den här metoden.

ReRegisterForFinalize Att anropa metoden garanterar inte att skräpinsamlaren anropar ett objekts slutversion.

Som standard läggs alla objekt som implementerar finalizers till i listan över objekt som kräver slutförande. Ett objekt kan dock redan ha slutförts eller inaktiverat slutförande genom att anropa SuppressFinalize metoden.

En slutförare kan använda den här metoden för att återuppväcka sig själv eller ett objekt som den refererar till.

Gäller för

Se även