BlockingCollection<T>.GetConsumingEnumerable BlockingCollection<T>.GetConsumingEnumerable BlockingCollection<T>.GetConsumingEnumerable BlockingCollection<T>.GetConsumingEnumerable Method

Provides a consuming IEnumerable<T> for items in the collection.

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>

Remarks

This method enables client code to remove items from the collection by using a foreach loop (For Each in Visual Basic), or Parallel.ForEach or a PLINQ query. The enumerator will continue to provide items (if any exist) until IsCompleted returns true, and if IsCompleted is false the loop blocks until an item becomes available or until the CancellationToken is cancelled.

Provides a consuming IEnumerator<T> for items in the collection.

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)

Examples

The following example shows how to use the GetConsumingEnumerable method:

class ConsumingEnumerableDemo
{
    // Demonstrates:
    //      BlockingCollection<T>.Add()
    //      BlockingCollection<T>.CompleteAdding()
    //      BlockingCollection<T>.GetConsumingEnumerable()
    public static void BC_GetConsumingEnumerable()
    {
        using (BlockingCollection<int> bc = new BlockingCollection<int>())
        {

            // Kick off a producer task
            Task.Factory.StartNew(() =>
            {
                for (int i = 0; i < 10; i++)
                {
                    bc.Add(i);
                    Thread.Sleep(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(item);
            }
        }
    }
}

'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 hanging
                    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