BatchBlock<T>.ISourceBlock<T[]>.ConsumeMessage Method

Definition

Namespace:

System.Threading.Tasks.Dataflow

Assembly:

System.Threading.Tasks.Dataflow.dll

Source:

BatchBlock.cs

Called by a linked ITargetBlock<TInput> to accept and consume a DataflowMessageHeader previously offered by this ISourceBlock<TOutput> .

C#

T[] ISourceBlock<T[]>.ConsumeMessage(System.Threading.Tasks.Dataflow.DataflowMessageHeader messageHeader, System.Threading.Tasks.Dataflow.ITargetBlock<T[]> target, out bool messageConsumed);

Parameters

messageHeader

DataflowMessageHeader

The DataflowMessageHeader of the message being consumed.

target

ITargetBlock<T[]>

The ITargetBlock<TInput> consuming the message.

messageConsumed

Boolean

true if the message was successfully consumed; otherwise, false.

Returns

T[]

The value of the consumed message. This may correspond to a different DataflowMessageHeader instance than was previously reserved and passed as the messageHeader to ConsumeMessage(DataflowMessageHeader, ITargetBlock<TOutput>, Boolean). The consuming ITargetBlock<TInput> must use the returned value instead of the value passed as messageValue through OfferMessage(DataflowMessageHeader, TInput, ISourceBlock<TInput>, Boolean).

If the message requested is not available, the return value will be null.

Implements

ConsumeMessage(DataflowMessageHeader, ITargetBlock<TOutput>, Boolean)

Exceptions

ArgumentException

The messageHeader is not valid.

ArgumentNullException

The target is null.

Remarks

Only ITargetBlock<TInput> instances linked to this ISourceBlock<TOutput> instance may use ConsumeMessage, and it must only be used to consume DataflowMessageHeader instances previously offered by this source to the target.

Applies to