Thread.GetData(LocalDataStoreSlot) Metode

Definisi

Ruang nama:
System.Threading
Rakitan:
netstandard.dll, System.Threading.Thread.dll
Rakitan:
System.Threading.Thread.dll
Rakitan:
mscorlib.dll
Rakitan:
netstandard.dll
Sumber:
Thread.cs
Sumber:
Thread.cs
Sumber:
Thread.cs
Sumber:
Thread.cs
Sumber:
Thread.cs

Mengambil nilai dari slot yang ditentukan pada utas saat ini, dalam domain utas saat ini. Untuk performa yang lebih baik, gunakan bidang yang ditandai dengan atribut sebagai gantinya ThreadStaticAttribute .

public:
 static System::Object ^ GetData(LocalDataStoreSlot ^ slot);
public static object? GetData(LocalDataStoreSlot slot);
public static object GetData(LocalDataStoreSlot slot);
static member GetData : LocalDataStoreSlot -> obj
Public Shared Function GetData (slot As LocalDataStoreSlot) As Object

Parameter

slot
LocalDataStoreSlot

dari LocalDataStoreSlot mana untuk mendapatkan nilai.

Mengembalikan

Object

Nilai yang diambil.

Contoh

Bagian ini berisi dua contoh kode. Contoh pertama menunjukkan cara menggunakan bidang yang ditandai dengan ThreadStaticAttribute atribut untuk menyimpan informasi khusus utas. Contoh kedua menunjukkan cara menggunakan slot data untuk melakukan hal yang sama.

Contoh Pertama

Contoh berikut menunjukkan cara menggunakan bidang yang ditandai dengan ThreadStaticAttribute untuk menyimpan informasi khusus utas. Teknik ini memberikan performa yang lebih baik daripada teknik yang ditunjukkan dalam contoh kedua.

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

Contoh Kedua

Contoh berikut menunjukkan cara menggunakan slot data untuk menyimpan informasi khusus utas.

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

Keterangan

Important

.NET Framework menyediakan dua mekanisme untuk menggunakan penyimpanan lokal utas (TLS): bidang statis relatif utas (yaitu, bidang yang ditandai dengan atribut ThreadStaticAttribute) dan slot data. Bidang statis relatif utas memberikan performa yang jauh lebih baik daripada slot data, dan mengaktifkan pemeriksaan jenis waktu kompilasi. Untuk informasi selengkapnya tentang menggunakan TLS, lihat Thread Local Storage: Thread-Relative Bidang Statis dan Slot Data.

Utas menggunakan mekanisme memori penyimpanan lokal untuk menyimpan data khusus utas. Runtime bahasa umum mengalokasikan array penyimpanan data multi-slot untuk setiap proses saat dibuat. Utas dapat mengalokasikan slot data di penyimpanan data, menyimpan dan mengambil nilai data di slot, dan membebaskan slot untuk digunakan kembali setelah utas kedaluwarsa. Slot data unik per utas. Tidak ada utas lain (bahkan utas anak) yang bisa mendapatkan data tersebut.

Note

GetData adalah Shared metode yang selalu berlaku untuk utas yang sedang dijalankan, bahkan jika Anda memanggilnya menggunakan variabel yang mengacu pada utas lain. Untuk menghindari kebingungan, gunakan nama kelas saat memanggil Shared metode: Dim test As Object = Thread.GetData(testSlot).

Berlaku untuk

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