Thread.GetNamedDataSlot(String) Méthode

Référence

Définition

Espace de noms:: System.Threading

Assembly:: System.Threading.Thread.dll

Assembly:: netstandard.dll

Assembly:: mscorlib.dll

Important

Certaines informations portent sur la préversion du produit qui est susceptible d’être en grande partie modifiée avant sa publication. Microsoft exclut toute garantie, expresse ou implicite, concernant les informations fournies ici.

Recherche un emplacement de données nommé. Pour de meilleures performances, utilisez à la place les champs marqués avec l'attribut ThreadStaticAttribute.

public:
 static LocalDataStoreSlot ^ GetNamedDataSlot(System::String ^ name);

public static LocalDataStoreSlot GetNamedDataSlot (string name);

static member GetNamedDataSlot : string -> LocalDataStoreSlot

Public Shared Function GetNamedDataSlot (name As String) As LocalDataStoreSlot

Paramètres

name: String

Nom de l'emplacement de données local.

Retours

LocalDataStoreSlot

LocalDataStoreSlot alloué pour ce thread.

Exemples

Cette section contient deux exemples de code. Le premier exemple montre comment utiliser un champ qui est marqué avec l' ThreadStaticAttribute attribut pour contenir des informations spécifiques au thread. Le deuxième exemple montre comment utiliser un emplacement de données pour effectuer la même opération.

Premier exemple

L’exemple suivant montre comment utiliser un champ marqué avec ThreadStaticAttribute pour conserver les informations spécifiques aux threads. Cette technique offre de meilleures performances que la technique présentée dans le deuxième exemple.

using namespace System;
using namespace System::Threading;

ref class ThreadData
{
private:
   [ThreadStatic]
   static int threadSpecificData;

public:
   static void ThreadStaticDemo()
   {
      // Store the managed thread id for each thread in the static
      // variable.
      threadSpecificData = Thread::CurrentThread->ManagedThreadId;
      
      // Allow other threads time to execute the same code, to show
      // that the static data is unique to each thread.
      Thread::Sleep( 1000 );

      // Display the static data.
      Console::WriteLine( "Data for managed thread {0}: {1}", 
         Thread::CurrentThread->ManagedThreadId, threadSpecificData );
   }
};

int main()
{
   for ( int i = 0; i < 3; i++ )
   {
      Thread^ newThread = 
          gcnew Thread( gcnew ThreadStart( ThreadData::ThreadStaticDemo )); 
      newThread->Start();
   }
}

/* This code example produces output similar to the following:

Data for managed thread 4: 4
Data for managed thread 5: 5
Data for managed thread 3: 3
 */

using System;
using System.Threading;

class Test
{
    static void Main()
    {
        for(int i = 0; i < 3; i++)
        {
            Thread newThread = new Thread(ThreadData.ThreadStaticDemo);
            newThread.Start();
        }
    }
}

class ThreadData
{
    [ThreadStatic]
    static int threadSpecificData;

    public static void ThreadStaticDemo()
    {
        // Store the managed thread id for each thread in the static
        // variable.
        threadSpecificData = Thread.CurrentThread.ManagedThreadId;
      
        // Allow other threads time to execute the same code, to show
        // that the static data is unique to each thread.
        Thread.Sleep( 1000 );

        // Display the static data.
        Console.WriteLine( "Data for managed thread {0}: {1}", 
            Thread.CurrentThread.ManagedThreadId, threadSpecificData );
    }
}

/* This code example produces output similar to the following:

Data for managed thread 4: 4
Data for managed thread 5: 5
Data for managed thread 3: 3
 */

Imports System.Threading

Class Test

    <MTAThread> _
    Shared Sub Main()

        For i As Integer = 1 To 3
            Dim newThread As New Thread(AddressOf ThreadData.ThreadStaticDemo)
            newThread.Start()
        Next i

    End Sub

End Class

Class ThreadData

    <ThreadStatic> _
    Shared threadSpecificData As Integer

    Shared Sub ThreadStaticDemo()

        ' Store the managed thread id for each thread in the static
        ' variable.
        threadSpecificData = Thread.CurrentThread.ManagedThreadId
      
        ' Allow other threads time to execute the same code, to show
        ' that the static data is unique to each thread.
        Thread.Sleep( 1000 )

        ' Display the static data.
        Console.WriteLine( "Data for managed thread {0}: {1}", _
            Thread.CurrentThread.ManagedThreadId, threadSpecificData )

    End Sub

End Class

' This code example produces output similar to the following:
'
'Data for managed thread 4: 4
'Data for managed thread 5: 5
'Data for managed thread 3: 3

Deuxième exemple

L’exemple suivant montre comment utiliser un emplacement de données nommé pour stocker des informations spécifiques au thread.

using namespace System;
using namespace System::Threading;

ref class Slot
{
private:
    static Random^ randomGenerator = gcnew Random();

public:
    static void SlotTest()
    {
        // Set random data in each thread's data slot.
        int slotData = randomGenerator->Next(1, 200);
        int threadId = Thread::CurrentThread->ManagedThreadId;

        Thread::SetData(
            Thread::GetNamedDataSlot("Random"),
            slotData);

        // Show what was saved in the thread's data slot.
        Console::WriteLine("Data stored in thread_{0}'s data slot: {1,3}",
            threadId, slotData);

        // Allow other threads time to execute SetData to show
        // that a thread's data slot is unique to itself.
        Thread::Sleep(1000);

        int newSlotData =
            (int)Thread::GetData(Thread::GetNamedDataSlot("Random"));

        if (newSlotData == slotData)
        {
            Console::WriteLine("Data in thread_{0}'s data slot is still: {1,3}",
                threadId, newSlotData);
        }
        else
        {
            Console::WriteLine("Data in thread_{0}'s data slot changed to: {1,3}",
                threadId, newSlotData);
        }
    }
};

ref class Test
{
public:
    static void Main()
    {
        array<Thread^>^ newThreads = gcnew array<Thread^>(4);
        int i;
        for (i = 0; i < newThreads->Length; i++)
        {
            newThreads[i] =
                gcnew Thread(gcnew ThreadStart(&Slot::SlotTest));
            newThreads[i]->Start();
        }
        Thread::Sleep(2000);
        for (i = 0; i < newThreads->Length; i++)
        {
            newThreads[i]->Join();
            Console::WriteLine("Thread_{0} finished.",
                newThreads[i]->ManagedThreadId);
        }
    }
};

int main()
{
    Test::Main();
}

using System;
using System.Threading;

class Test
{
    public static void Main()
    {
        Thread[] newThreads = new Thread[4];
        int i;
        for (i = 0; i < newThreads.Length; i++)
        {
            newThreads[i] =
                new Thread(new ThreadStart(Slot.SlotTest));
            newThreads[i].Start();
        }
        Thread.Sleep(2000);
        for (i = 0; i < newThreads.Length; i++)
        {
            newThreads[i].Join();
            Console.WriteLine("Thread_{0} finished.",
                newThreads[i].ManagedThreadId);
        }
    }
}

class Slot
{
    private static Random randomGenerator = new Random();

    public static void SlotTest()
    {
        // Set random data in each thread's data slot.
        int slotData = randomGenerator.Next(1, 200);
        int threadId = Thread.CurrentThread.ManagedThreadId;

        Thread.SetData(
            Thread.GetNamedDataSlot("Random"),
            slotData);

        // Show what was saved in the thread's data slot.
        Console.WriteLine("Data stored in thread_{0}'s data slot: {1,3}",
            threadId, slotData);

        // Allow other threads time to execute SetData to show
        // that a thread's data slot is unique to itself.
        Thread.Sleep(1000);

        int newSlotData =
            (int)Thread.GetData(Thread.GetNamedDataSlot("Random"));

        if (newSlotData == slotData)
        {
            Console.WriteLine("Data in thread_{0}'s data slot is still: {1,3}",
                threadId, newSlotData);
        }
        else
        {
            Console.WriteLine("Data in thread_{0}'s data slot changed to: {1,3}",
                threadId, newSlotData);
        }
    }
}

Imports System.Threading

Class Test
    Public Shared Sub Main()
        Dim newThreads(3) As Thread
        Dim i As Integer
        For i = 0 To newThreads.Length - 1
            newThreads(i) = _
                New Thread(New ThreadStart(AddressOf Slot.SlotTest))
            newThreads(i).Start()
        Next i
        Thread.Sleep(2000)
        For i = 0 To newThreads.Length - 1
            newThreads(i).Join()
            Console.WriteLine("Thread_{0} finished.", _
                newThreads(i).ManagedThreadId)
        Next i
    End Sub
End Class

Class Slot
    Private Shared randomGenerator As New Random()

    Public Shared Sub SlotTest()
        ' Set random data in each thread's data slot.
        Dim slotData As Integer = randomGenerator.Next(1, 200)
        Dim threadId As Integer = Thread.CurrentThread.ManagedThreadId

        Thread.SetData(
            Thread.GetNamedDataSlot("Random"),
            slotData)

        ' Show what was saved in the thread's data slot.
        Console.WriteLine("Data stored in thread_{0}'s data slot: {1,3}",
            threadId, slotData)

        ' Allow other threads time to execute SetData to show
        ' that a thread's data slot is unique to itself.
        Thread.Sleep(1000)

        Dim newSlotData As Integer = _
            CType(Thread.GetData(Thread.GetNamedDataSlot("Random")), Integer)

        If newSlotData = slotData Then
            Console.WriteLine("Data in thread_{0}'s data slot is still: {1,3}",
                threadId, newSlotData)
        Else
            Console.WriteLine("Data in thread_{0}'s data slot changed to: {1,3}",
                threadId, newSlotData)
        End If
    End Sub
End Class

Remarques

Important

.NET Framework fournit deux mécanismes pour l’utilisation du stockage local des threads (TLS) : les champs statiques relatifs à un thread (autrement dit, les champs marqués avec l' ThreadStaticAttribute attribut) et les emplacements de données. Les champs statiques relatifs à un thread offrent de meilleures performances que les emplacements de données et activent la vérification de type au moment de la compilation. pour plus d’informations sur l’utilisation de TLS, consultez Thread Local Stockage : Thread-Relative les champs statiques et les emplacements de données.

Les threads utilisent un mécanisme de mémoire de stockage local pour stocker des données spécifiques aux threads. Le common language runtime alloue un groupe de magasins de données à plusieurs emplacements à chaque processus lors de sa création. Le thread peut allouer un emplacement de données dans le magasin de données, stocker et récupérer une valeur de données dans l’emplacement, puis libérer l’emplacement en vue de sa réutilisation après l’expiration du thread. Les emplacements de données sont uniques par thread. Aucun autre thread (pas même un thread enfant) ne peut obtenir ces données.

Si l’emplacement nommé n’existe pas, un nouvel emplacement est alloué. Les emplacements de données nommés sont publics et peuvent être manipulés par n’importe qui.

S’applique à

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