Stream.ReadExactlyAsync Method

Definition

Namespace:

System.IO

Assembly:

System.Runtime.dll

Overloads

ReadExactlyAsync(Memory<Byte>, CancellationToken)	Asynchronously reads bytes from the current stream, advances the position within the stream until the buffer is filled, and monitors cancellation requests.
ReadExactlyAsync(Byte[], Int32, Int32, CancellationToken)	Asynchronously reads count number of bytes from the current stream, advances the position within the stream, and monitors cancellation requests.

ReadExactlyAsync(Memory<Byte>, CancellationToken)

Source:

Stream.cs

Asynchronously reads bytes from the current stream, advances the position within the stream until the buffer is filled, and monitors cancellation requests.

public System.Threading.Tasks.ValueTask ReadExactlyAsync (Memory<byte> buffer, System.Threading.CancellationToken cancellationToken = default);

member this.ReadExactlyAsync : Memory<byte> * System.Threading.CancellationToken -> System.Threading.Tasks.ValueTask

Public Function ReadExactlyAsync (buffer As Memory(Of Byte), Optional cancellationToken As CancellationToken = Nothing) As ValueTask

Parameters

buffer

Memory<Byte>

The buffer to write the data into.

cancellationToken

CancellationToken

The token to monitor for cancellation requests.

Returns

ValueTask

A task that represents the asynchronous read operation.

Exceptions

EndOfStreamException

The end of the stream is reached before filling the buffer.

OperationCanceledException

The cancellation token was canceled. This exception is stored into the returned task.

Remarks

When buffer is empty, this read operation will be completed without waiting for available data in the stream.

ReadExactlyAsync(Byte[], Int32, Int32, CancellationToken)

Source:

Stream.cs

Asynchronously reads count number of bytes from the current stream, advances the position within the stream, and monitors cancellation requests.

public System.Threading.Tasks.ValueTask ReadExactlyAsync (byte[] buffer, int offset, int count, System.Threading.CancellationToken cancellationToken = default);

member this.ReadExactlyAsync : byte[] * int * int * System.Threading.CancellationToken -> System.Threading.Tasks.ValueTask

Public Function ReadExactlyAsync (buffer As Byte(), offset As Integer, count As Integer, Optional cancellationToken As CancellationToken = Nothing) As ValueTask

Parameters

buffer

Byte[]

The buffer to write the data into.

offset

Int32

The byte offset in buffer at which to begin writing data from the stream.

count

Int32

The number of bytes to be read from the current stream.

cancellationToken

CancellationToken

The token to monitor for cancellation requests.

Returns

ValueTask

A task that represents the asynchronous read operation.

Exceptions

ArgumentNullException

buffer is null.

ArgumentOutOfRangeException

offset is outside the bounds of buffer.

-or-

count is negative.

-or-

The range specified by the combination of offset and count exceeds the length of buffer.

EndOfStreamException

The end of the stream is reached before reading count number of bytes.

OperationCanceledException

The cancellation token was canceled. This exception is stored into the returned task.

Remarks

When count is 0 (zero), this read operation will be completed without waiting for available data in the stream.

This method stores in the task it returns all non-usage exceptions that the method's synchronous counterpart can throw. If an exception is stored into the returned task, that exception will be thrown when the task is awaited. Usage exceptions, such as ArgumentException, are still thrown synchronously. For the stored exceptions, see the exceptions thrown by ReadExactly(Byte[], Int32, Int32).