IProducerConsumerCollection<T> Interface

Définition

generic <typename T>
public interface class IProducerConsumerCollection : System::Collections::Generic::IEnumerable<T>, System::Collections::ICollection

public interface IProducerConsumerCollection<T> : System.Collections.Generic.IEnumerable<T>, System.Collections.ICollection

type IProducerConsumerCollection<'T> = interface
    interface seq<'T>
    interface ICollection
    interface IEnumerable

Public Interface IProducerConsumerCollection(Of T)
Implements ICollection, IEnumerable(Of T)

Paramètres de type

Dérivé

System.Collections.Concurrent.ConcurrentBag<T>

System.Collections.Concurrent.ConcurrentQueue<T>

System.Collections.Concurrent.ConcurrentStack<T>

Implémente

IEnumerable<T> ICollection IEnumerable

Exemples

L’exemple suivant montre une structure de données de pile qui implémente System.Collections.Concurrent.IProducerConsumerCollection<T>.The following example shows a stack data structure that implements System.Collections.Concurrent.IProducerConsumerCollection<T>.

using System;
using System.Collections;
using System.Collections.Generic;
using System.Collections.Concurrent;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;


// Sample implementation of IProducerConsumerCollection(T) 
// -- in this case, a thread-safe stack.
public class SafeStack<T> : IProducerConsumerCollection<T>
{
    // Used for enforcing thread-safety
    private object m_lockObject = new object();

    // We'll use a regular old Stack for our core operations
    private Stack<T> m_sequentialStack = null;

    //
    // Constructors
    //
    public SafeStack()
    {
        m_sequentialStack = new Stack<T>();
    }

    public SafeStack(IEnumerable<T> collection)
    {
        m_sequentialStack = new Stack<T>(collection);
    }

    //
    // Safe Push/Pop support
    //
    public void Push(T item)
    {
        lock (m_lockObject) m_sequentialStack.Push(item);
    }

    public bool TryPop(out T item)
    {
        bool rval = true;
        lock (m_lockObject)
        {
            if (m_sequentialStack.Count == 0) { item = default(T); rval = false; }
            else item = m_sequentialStack.Pop();
        }
        return rval;
    }

    //
    // IProducerConsumerCollection(T) support
    //
    public bool TryTake(out T item)
    {
        return TryPop(out item);
    }

    public bool TryAdd(T item)
    {
        Push(item);
        return true; // Push doesn't fail
    }

    public T[] ToArray()
    {
        T[] rval = null;
        lock (m_lockObject) rval = m_sequentialStack.ToArray();
        return rval;
    }

    public void CopyTo(T[] array, int index)
    {
        lock (m_lockObject) m_sequentialStack.CopyTo(array, index);
    }



    //
    // Support for IEnumerable(T)
    //
    public IEnumerator<T> GetEnumerator()
    {
        // The performance here will be unfortunate for large stacks,
        // but thread-safety is effectively implemented.
        Stack<T> stackCopy = null;
        lock (m_lockObject) stackCopy = new Stack<T>(m_sequentialStack);
        return stackCopy.GetEnumerator();
    }


    //
    // Support for IEnumerable
    //
    IEnumerator IEnumerable.GetEnumerator()
    {
        return ((IEnumerable<T>)this).GetEnumerator();
    }

    // 
    // Support for ICollection
    //
    public bool IsSynchronized
    {
        get { return true; }
    }

    public object SyncRoot
    {
        get { return m_lockObject; }
    }

    public int Count
    {
        get { return m_sequentialStack.Count; }
    }

    public void CopyTo(Array array, int index)
    {
        lock (m_lockObject) ((ICollection)m_sequentialStack).CopyTo(array, index);
    }
}

public class Program
{
    static void Main()
    {
        TestSafeStack();

        // Keep the console window open in debug mode.
        Console.WriteLine("Press any key to exit.");
        Console.ReadKey();
    }

    // Test our implementation of IProducerConsumerCollection(T)
    // Demonstrates:
    //      IPCC(T).TryAdd()
    //      IPCC(T).TryTake()
    //      IPCC(T).CopyTo()
    static void TestSafeStack()
    {
        SafeStack<int> stack = new SafeStack<int>();
        IProducerConsumerCollection<int> ipcc = (IProducerConsumerCollection<int>)stack;

        // Test Push()/TryAdd()
        stack.Push(10); Console.WriteLine("Pushed 10");
        ipcc.TryAdd(20); Console.WriteLine("IPCC.TryAdded 20");
        stack.Push(15); Console.WriteLine("Pushed 15");

        int[] testArray = new int[3];

        // Try CopyTo() within boundaries
        try
        {
            ipcc.CopyTo(testArray, 0);
            Console.WriteLine("CopyTo() within boundaries worked, as expected");
        }
        catch (Exception e)
        {
            Console.WriteLine("CopyTo() within boundaries unexpectedly threw an exception: {0}", e.Message);
        }

        // Try CopyTo() that overflows
        try
        {
            ipcc.CopyTo(testArray, 1);
            Console.WriteLine("CopyTo() with index overflow worked, and it SHOULD NOT HAVE");
        }
        catch (Exception e)
        {
            Console.WriteLine("CopyTo() with index overflow threw an exception, as expected: {0}", e.Message);
        }

        // Test enumeration
        Console.Write("Enumeration (should be three items): ");
        foreach (int item in stack) Console.Write("{0} ", item);
        Console.WriteLine("");

        // Test TryPop()
        int popped = 0;
        if (stack.TryPop(out popped))
        {
            Console.WriteLine("Successfully popped {0}", popped);
        }
        else Console.WriteLine("FAILED to pop!!");

        // Test Count
        Console.WriteLine("stack count is {0}, should be 2", stack.Count);

        // Test TryTake()
        if (ipcc.TryTake(out popped))
        {
            Console.WriteLine("Successfully IPCC-TryTaked {0}", popped);
        }
        else Console.WriteLine("FAILED to IPCC.TryTake!!");
    }
}

Imports System.Collections.Concurrent

Module IProdCon
    ' Sample implementation of IProducerConsumerCollection(T) -- in this case,
    ' a thread-safe stack.
    Public Class SafeStack(Of T)
        Implements IProducerConsumerCollection(Of T)

        ' Used for enforcing thread-safety
        Private m_lockObject As New Object()

        ' We'll use a regular old Stack for our core operations
        Private m_sequentialStack As Stack(Of T) = Nothing

        '
        ' Constructors
        '
        Public Sub New()
            m_sequentialStack = New Stack(Of T)()
        End Sub

        Public Sub New(ByVal collection As IEnumerable(Of T))
            m_sequentialStack = New Stack(Of T)(collection)
        End Sub

        '
        ' Safe Push/Pop support
        '
        Public Sub Push(ByVal item As T)
            SyncLock m_lockObject
                m_sequentialStack.Push(item)
            End SyncLock
        End Sub

        Public Function TryPop(ByRef item As T) As Boolean
            Dim rval As Boolean = True
            SyncLock m_lockObject
                If m_sequentialStack.Count = 0 Then
                    item = Nothing
                    rval = False
                Else
                    item = m_sequentialStack.Pop()
                End If
            End SyncLock
            Return rval
        End Function

        '
        ' IProducerConsumerCollection(T) support
        '
        Public Function TryTake(ByRef item As T) As Boolean Implements IProducerConsumerCollection(Of T).TryTake
            Return TryPop(item)
        End Function

        Public Function TryAdd(ByVal item As T) As Boolean Implements IProducerConsumerCollection(Of T).TryAdd
            Push(item)
            ' Push doesn't fail
            Return True
        End Function

        Public Function ToArray() As T() Implements IProducerConsumerCollection(Of T).ToArray
            Dim rval As T() = Nothing
            SyncLock m_lockObject
                rval = m_sequentialStack.ToArray()
            End SyncLock
            Return rval
        End Function

        Public Sub CopyTo(ByVal array As T(), ByVal index As Integer) Implements IProducerConsumerCollection(Of T).CopyTo
            SyncLock m_lockObject
                m_sequentialStack.CopyTo(array, index)
            End SyncLock
        End Sub



        '
        ' Support for IEnumerable(T)
        '
        Public Function GetEnumerator() As IEnumerator(Of T) Implements IEnumerable(Of T).GetEnumerator
            ' The performance here will be unfortunate for large stacks,
            ' but thread-safety is effectively implemented.
            Dim stackCopy As Stack(Of T) = Nothing
            SyncLock m_lockObject
                stackCopy = New Stack(Of T)(m_sequentialStack)
            End SyncLock
            Return stackCopy.GetEnumerator()
        End Function


        '
        ' Support for IEnumerable
        '
        Private Function GetEnumerator2() As IEnumerator Implements IEnumerable.GetEnumerator
            Return DirectCast(Me, IEnumerable(Of T)).GetEnumerator()
        End Function

        ' 
        ' Support for ICollection
        '
        Public ReadOnly Property IsSynchronized() As Boolean Implements ICollection.IsSynchronized
            Get
                Return True
            End Get
        End Property

        Public ReadOnly Property SyncRoot() As Object Implements ICollection.SyncRoot
            Get
                Return m_lockObject
            End Get
        End Property

        Public ReadOnly Property Count() As Integer Implements ICollection.Count
            Get
                Return m_sequentialStack.Count
            End Get
        End Property

        Public Sub CopyTo(ByVal array As Array, ByVal index As Integer) Implements ICollection.CopyTo
            SyncLock m_lockObject
                DirectCast(m_sequentialStack, ICollection).CopyTo(array, index)
            End SyncLock
        End Sub
    End Class

    ' Test our implementation of IProducerConsumerCollection(T)
    ' Demonstrates:
    ' IPCC(T).TryAdd()
    ' IPCC(T).TryTake()
    ' IPCC(T).CopyTo()
    Private Sub TestSafeStack()
        Dim stack As New SafeStack(Of Integer)()
        Dim ipcc As IProducerConsumerCollection(Of Integer) = DirectCast(stack, IProducerConsumerCollection(Of Integer))

        ' Test Push()/TryAdd()
        stack.Push(10)
        Console.WriteLine("Pushed 10")
        ipcc.TryAdd(20)
        Console.WriteLine("IPCC.TryAdded 20")
        stack.Push(15)
        Console.WriteLine("Pushed 15")

        Dim testArray As Integer() = New Integer(2) {}

        ' Try CopyTo() within boundaries
        Try
            ipcc.CopyTo(testArray, 0)
            Console.WriteLine("CopyTo() within boundaries worked, as expected")
        Catch e As Exception
            Console.WriteLine("CopyTo() within boundaries unexpectedly threw an exception: {0}", e.Message)
        End Try

        ' Try CopyTo() that overflows
        Try
            ipcc.CopyTo(testArray, 1)
            Console.WriteLine("CopyTo() with index overflow worked, and it SHOULD NOT HAVE")
        Catch e As Exception
            Console.WriteLine("CopyTo() with index overflow threw an exception, as expected: {0}", e.Message)
        End Try

        ' Test enumeration
        Console.Write("Enumeration (should be three items): ")
        For Each item As Integer In stack
            Console.Write("{0} ", item)
        Next
        Console.WriteLine("")

        ' Test TryPop()
        Dim popped As Integer = 0
        If stack.TryPop(popped) Then
            Console.WriteLine("Successfully popped {0}", popped)
        Else
            Console.WriteLine("FAILED to pop!!")
        End If

        ' Test Count
        Console.WriteLine("stack count is {0}, should be 2", stack.Count)

        ' Test TryTake()
        If ipcc.TryTake(popped) Then
            Console.WriteLine("Successfully IPCC-TryTaked {0}", popped)
        Else
            Console.WriteLine("FAILED to IPCC.TryTake!!")
        End If
    End Sub

    Sub Main()
        TestSafeStack()

        ' Keep the console window open in debug mode
        Console.WriteLine("Press any key to exit.")
        Console.ReadKey()

    End Sub

End Module

Remarques

Pour plus d’informations, consultez collections thread-safe et vue d’ensemble de BlockingCollection.For more information, see Thread-Safe Collections and BlockingCollection Overview.

Propriétés

Méthodes

Méthodes d’extension

S’applique à

Cohérence de thread

Toutes les implémentations de cette interface doivent permettre l’utilisation simultanée de tous les membres de cette interface à partir de plusieurs threads.All implementations of this interface must enable all members of this interface to be used concurrently from multiple threads.

Voir aussi

• Procédure : Ajouter des fonctionnalités de délimitation et de blocage à une classe de collectionHow to: Add Bounding and Blocking Functionality to a Collection Class