IRecordSequence.BeginAppend Method (IList<ArraySegment<Byte>>, SequenceNumber, SequenceNumber, RecordAppendOptions, ReservationCollection, AsyncCallback, Object)


When overridden in a derived class, begins an asynchronous append operation, using space previously reserved in the sequence.

Namespace:   System.IO.Log
Assembly:  System.IO.Log (in System.IO.Log.dll)

IAsyncResult BeginAppend(
	IList<ArraySegment<byte>> data,
	SequenceNumber nextUndoRecord,
	SequenceNumber previousUndoRecord,
	RecordAppendOptions recordAppendOptions,
	ReservationCollection reservations,
	AsyncCallback callback,
	object state


Type: System.Collections.Generic.IList<ArraySegment<Byte>>

A list of byte array segments that will be concatenated and appended as the record.

Type: System.IO.Log.SequenceNumber

The sequence number of the next record in the user-specified order.

Type: System.IO.Log.SequenceNumber

The sequence number of the next record in Previous order.

Type: System.IO.Log.RecordAppendOptions

A valid value of RecordAppendOptions that specifies how the data should be written.

Type: System.IO.Log.ReservationCollection

A ReservationCollection that contains the reservation that should be used for this record.

Type: System.AsyncCallback

An optional asynchronous callback, to be called when the append is complete.

Type: System.Object

A user-provided object that distinguishes this particular asynchronous append request from other requests.

Return Value

Type: System.IAsyncResult

An IAsyncResult that represents the asynchronous append, which could still be pending.

Exception Condition

One or more of the arguments is invalid.


An I/O error occurred while appending the record.


The record sequence could not make enough free space to contain the new record.


The method was called after the sequence has been disposed of.

You should pass the IAsyncResult returned by this method to the EndAppend method to ensure that the append operation has completed and resources can be freed appropriately. If an error has occurred during an asynchronous append, an exception is not thrown until the EndAppend method is called with the IAsyncResult returned by this method.

Data contained in the data parameter will be concatenated into a single byte array for appending as the record. However, no provision is made for splitting data back into array segments when the record is read.

The appended record will consume space that has been previously reserved, using a reservation specified by the reservations parameter. If the append succeeds, it will consume the smallest reservation area that can hold the data, and that reservation area will be removed from the collection.

Normally, this method completes before the record has been written. To ensure that a record has been written, either specify the ForceFlush flag using the recordAppendOptions parameter, or call the Flush method.

.NET Framework
Available since 3.0
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