Thread.AllocateDataSlot Metod

public:
 static LocalDataStoreSlot ^ AllocateDataSlot();

public static LocalDataStoreSlot AllocateDataSlot();

static member AllocateDataSlot : unit -> LocalDataStoreSlot

Public Shared Function AllocateDataSlot () As LocalDataStoreSlot

Returer

Det allokerade namngivna datafacket i alla trådar.

Exempel

Det här avsnittet innehåller två kodexempel. Det första exemplet visar hur du använder ett fält som är markerat med ThreadStaticAttribute attributet för att lagra trådspecifik information. Det andra exemplet visar hur du använder ett datafack för att göra samma sak.

Första exemplet

I följande exempel visas hur du använder ett fält som är markerat med ThreadStaticAttribute för att lagra trådspecifik information. Den här tekniken ger bättre prestanda än den teknik som visas i det andra exemplet.

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
 */

open System
open System.Threading

type ThreadData() =
    // Create a static variable to hold the data for each thread.
    [<ThreadStatic; DefaultValue>]
    static val mutable private threadSpecificData : int

    static member ThreadStaticDemo() =
        // Store the managed thread id for each thread in the static
        // variable.
        ThreadData.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.
        printfn $"Data for managed thread {Thread.CurrentThread.ManagedThreadId}: {ThreadData.threadSpecificData}" 

for i = 0 to 2 do 
    let newThread = Thread 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

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

Andra exemplet

Följande kodexempel visar hur du använder ett datafack för att lagra trådspecifik information.

using System;
using System.Threading;

class Test
{
    static void Main()
    {
        Thread[] newThreads = new Thread[4];
        for(int i = 0; i < newThreads.Length; i++)
        {
            newThreads[i] = new Thread(
                new ThreadStart(Slot.SlotTest));
            newThreads[i].Start();
        }
    }
}

class Slot
{
    static Random randomGenerator;
    static LocalDataStoreSlot localSlot;

    static Slot()
    {
        randomGenerator = new Random();
        localSlot = Thread.AllocateDataSlot();
    }

    public static void SlotTest()
    {
        // Set different data in each thread's data slot.
        Thread.SetData(localSlot, randomGenerator.Next(1, 200));

        // Write the data from each thread's data slot.
        Console.WriteLine("Data in thread_{0}'s data slot: {1,3}", 
            AppDomain.GetCurrentThreadId().ToString(),
            Thread.GetData(localSlot).ToString());

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

        Console.WriteLine("Data in thread_{0}'s data slot: {1,3}", 
            AppDomain.GetCurrentThreadId().ToString(),
            Thread.GetData(localSlot).ToString());
    }
}

open System
open System.Threading

module Slot =
    let randomGenerator = Random()
    let localSlot = Thread.AllocateDataSlot()


    let slotTest () =
        // Set different data in each thread's data slot.
        Thread.SetData(localSlot, randomGenerator.Next(1, 200))

        // Write the data from each thread's data slot.
        printfn $"Data in thread_{AppDomain.GetCurrentThreadId()}'s data slot: {Thread.GetData localSlot, 3}"

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

        printfn $"Data in thread_{AppDomain.GetCurrentThreadId()}'s data slot: {Thread.GetData localSlot, 3}"

let newThreads =
    [| for _ = 0 to 3 do
           let thread = Thread Slot.slotTest
           thread.Start()
           thread |]

Imports System.Threading

Class Test

    <MTAThread> _
    Shared Sub Main()
        Dim newThreads(3) As Thread
        For i As Integer = 0 To newThreads.Length - 1
            newThreads(i) = New Thread(AddressOf Slot.SlotTest)
            newThreads(i).Start()
        Next i
    End Sub

End Class

Public Class Slot

    Shared randomGenerator As Random
    Shared localSlot As LocalDataStoreSlot

    Shared Sub New()
        randomGenerator = new Random()
        localSlot = Thread.AllocateDataSlot()
    End Sub

    Shared Sub SlotTest()

        ' Set different data in each thread's data slot.
        Thread.SetData(localSlot, randomGenerator.Next(1, 200))

        ' Write the data from each thread's data slot.
        Console.WriteLine("Data in thread_{0}'s data slot: {1,3}", _
            AppDomain.GetCurrentThreadId().ToString(), _
            Thread.GetData(localSlot).ToString())

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

        ' Write the data from each thread's data slot.
        Console.WriteLine("Data in thread_{0}'s data slot: {1,3}", _
            AppDomain.GetCurrentThreadId().ToString(), _
            Thread.GetData(localSlot).ToString())
    End Sub

End Class

Kommentarer

Facket allokeras på alla trådar.

Trådar använder en lokal lagringsminnesmekanism för att lagra trådspecifika data. Den vanliga språkkörningen allokerar en matris för datalager med flera platser till varje process när den skapas. Tråden kan allokera ett datafack i datalagret, lagra och hämta ett datavärde i facket och frigöra facket för återanvändning när tråden upphör att gälla. Datafack är unika per tråd. Ingen annan tråd (inte ens en underordnad tråd) kan hämta dessa data.

Se även

• Trådar och gängning
• Trådlokal lagring: Thread-Relative statiska fält och datafack