BlockingCollection<T>.GetConsumingEnumerable Método

public:
 System::Collections::Generic::IEnumerable<T> ^ GetConsumingEnumerable(System::Threading::CancellationToken cancellationToken);

public System.Collections.Generic.IEnumerable<T> GetConsumingEnumerable(System.Threading.CancellationToken cancellationToken);

member this.GetConsumingEnumerable : System.Threading.CancellationToken -> seq<'T>

Public Function GetConsumingEnumerable (cancellationToken As CancellationToken) As IEnumerable(Of T)

Public Iterator Function GetConsumingEnumerable (cancellationToken As CancellationToken) As IEnumerable(Of T)

Parâmetros

Retornos

Um IEnumerable<T> que remove e retorna itens da coleção.

Exceções

Comentários

Esse método permite que o código do cliente remova itens da coleção usando um loop foreach (For Each in Visual Basic) ou Parallel.ForEach ou uma consulta PLINQ. O enumerador continuará fornecendo itens (se houver algum) até IsCompleted retornar true e, se IsCompleted for falso, os blocos de loop até que um item fique disponível ou até que seja CancellationToken cancelado.

Confira também

• ColeçõesThread-Safe
• Visão geral de BlockingCollection

public:
 System::Collections::Generic::IEnumerable<T> ^ GetConsumingEnumerable();

public System.Collections.Generic.IEnumerable<T> GetConsumingEnumerable();

member this.GetConsumingEnumerable : unit -> seq<'T>

Public Function GetConsumingEnumerable () As IEnumerable(Of T)

Retornos

Um IEnumerable<T> que remove e retorna itens da coleção.

Exceções

Exemplos

O seguinte exemplo mostra como usar o método GetConsumingEnumerable:

class ConsumingEnumerableDemo
{
    // Demonstrates:
    //      BlockingCollection<T>.Add()
    //      BlockingCollection<T>.CompleteAdding()
    //      BlockingCollection<T>.GetConsumingEnumerable()
    public static async Task BC_GetConsumingEnumerable()
    {
        using (BlockingCollection<int> bc = new BlockingCollection<int>())
        {
            // Kick off a producer task
            var producerTask = Task.Run(async () =>
            {
                for (int i = 0; i < 10; i++)
                {
                    bc.Add(i);
                    Console.WriteLine($"Producing: {i}");

                    await Task.Delay(100); // sleep 100 ms between adds
                }

                // Need to do this to keep foreach below from hanging
                bc.CompleteAdding();
            });

            // Now consume the blocking collection with foreach.
            // Use bc.GetConsumingEnumerable() instead of just bc because the
            // former will block waiting for completion and the latter will
            // simply take a snapshot of the current state of the underlying collection.
            foreach (var item in bc.GetConsumingEnumerable())
            {
                Console.WriteLine($"Consuming: {item}");
            }
            await producerTask; // Allow task to complete cleanup
        }
    }
}

module ConsumingEnumerableDemo =
    // Demonstrates:
    //      BlockingCollection<T>.Add()
    //      BlockingCollection<T>.CompleteAdding()
    //      BlockingCollection<T>.GetConsumingEnumerable()
    let blockingCollectionGetConsumingEnumerable () =
        task {
            use bc = new BlockingCollection<int>()
            // Kick off a producer task
            let producerTask =
                task {
                    for i = 0 to 9 do
                        bc.Add i
                        printfn $"Producing: {i}"

                        do! Task.Delay 100 // sleep 100 ms between adds
                    // Need to do this to keep foreach below from hanging
                    bc.CompleteAdding()
                }

            // Now consume the blocking collection with foreach.
            // Use bc.GetConsumingEnumerable() instead of just bc because the
            // former will block waiting for completion and the latter will
            // simply take a snapshot of the current state of the underlying collection.
            for item in bc.GetConsumingEnumerable() do
                printfn $"Consuming: {item}"
            do! producerTask // Allow task to complete cleanup
        }

'Imports System.Threading.Tasks
'Imports System.Collections.Concurrent

' Demonstrates:
' BlockingCollection<T>.Add()
' BlockingCollection<T>.CompleteAdding()
' BlockingCollection<T>.GetConsumingEnumerable()

Class ConsumingEnumerableDemo
    Shared Sub BC_GetConsumingEnumerable()
        Using bc As New BlockingCollection(Of Integer)()

            ' Kick off a producer task
            Task.Factory.StartNew(
                Sub()
                    For i As Integer = 0 To 9
                        bc.Add(i)
                        ' sleep 100 ms between adds
                        Thread.Sleep(100)
                    Next

                    ' Need to do this to keep foreach below from not responding.
                    bc.CompleteAdding()
                End Sub)
            ' Now consume the blocking collection with foreach.
            ' Use bc.GetConsumingEnumerable() instead of just bc because the
            ' former will block waiting for completion and the latter will
            ' simply take a snapshot of the current state of the underlying collection.
            For Each item In bc.GetConsumingEnumerable()
                Console.WriteLine(item)
            Next
        End Using
    End Sub
End Class

Confira também

• ColeçõesThread-Safe
• Visão geral de BlockingCollection