LogRecordSequence.BeginReserveAndAppend Method (IList<ArraySegment<Byte>>, SequenceNumber, SequenceNumber, RecordAppendOptions, ReservationCollection, Int64[], AsyncCallback, Object)


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Begins an asynchronous reserve and append operation. This method cannot be inherited.

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

public IAsyncResult BeginReserveAndAppend(
	IList<ArraySegment<byte>> data,
	SequenceNumber userRecord,
	SequenceNumber previousRecord,
	RecordAppendOptions recordAppendOptions,
	ReservationCollection reservationCollection,
	long[] 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

The reservation collection to make reservations in.

Type: System.Int64[]

The reservations to make, in bytes.

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 this asynchronous operation, 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, or to make the reservation.


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

You should pass the IAsyncResult returned by this method to the EndReserveAndAppend 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 EndReserveAndAppend 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 specified reservations are added to the provided reservation collection in an atomic operation with a record append operation. If the append fails, no space is reserved.

Normally, this method may complete 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.

If a record sequence has been disposed of, or if you pass an invalid argument, exceptions are thrown immediately within this operation. Errors that occurred during an asynchronous append request, for example, a disk failure during the I/O request, will result in exceptions being thrown when the EndReserveAndAppend method is called.

.NET Framework
Available since 3.0
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