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WriteAsync(ReadOnlyMemory<Byte>, CancellationToken) |
Asynchronously writes a sequence of bytes to the current buffered stream, advances the current position within this buffered stream by the number of bytes written, and monitors cancellation requests. |
WriteAsync(Byte[], Int32, Int32, CancellationToken) |
Asynchronously writes a sequence of bytes to the current stream, advances the current position within this stream by the number of bytes written, and monitors cancellation requests. |
Asynchronously writes a sequence of bytes to the current buffered stream, advances the current position within this buffered stream by the number of bytes written, and monitors cancellation requests.
public override System.Threading.Tasks.ValueTask WriteAsync(ReadOnlyMemory<byte> buffer, System.Threading.CancellationToken cancellationToken = default);
override this.WriteAsync : ReadOnlyMemory<byte> * System.Threading.CancellationToken -> System.Threading.Tasks.ValueTask
Public Overrides Function WriteAsync (buffer As ReadOnlyMemory(Of Byte), Optional cancellationToken As CancellationToken = Nothing) As ValueTask
The region of memory to write data from.
The token to monitor for cancellation requests. The default value is None.
A task that represents the asynchronous write operation.
The cancellation token was canceled. This exception is stored into the returned task.
The WriteAsync
method enables you to perform resource-intensive I/O operations without blocking the main thread. This performance consideration is particularly important in a Windows 8.x Store app or desktop app where a time-consuming stream operation can block the UI thread and make your app appear as if it is not working. The async methods are used in conjunction with the async
and await
keywords in Visual Basic and C#.
Use the CanWrite property to determine whether the current instance supports writing.
If the operation is canceled before it completes, the returned task contains the TaskStatus.Canceled value for the Task.Status property.
Product | Versions |
---|---|
.NET | Core 3.0, Core 3.1, 5, 6, 7, 8, 9, 10 |
Asynchronously writes a sequence of bytes to the current stream, advances the current position within this stream by the number of bytes written, and monitors cancellation requests.
public:
override System::Threading::Tasks::Task ^ WriteAsync(cli::array <System::Byte> ^ buffer, int offset, int count, System::Threading::CancellationToken cancellationToken);
public override System.Threading.Tasks.Task WriteAsync(byte[] buffer, int offset, int count, System.Threading.CancellationToken cancellationToken);
override this.WriteAsync : byte[] * int * int * System.Threading.CancellationToken -> System.Threading.Tasks.Task
Public Overrides Function WriteAsync (buffer As Byte(), offset As Integer, count As Integer, cancellationToken As CancellationToken) As Task
The buffer to write data from.
The zero-based byte offset in buffer
from which to begin copying bytes to the stream.
The maximum number of bytes to write.
The token to monitor for cancellation requests.
A task that represents the asynchronous write operation.
buffer
is null
.
offset
or count
is negative.
The sum of offset
and count
is larger than the buffer length.
The stream does not support writing.
The stream has been disposed.
The stream is currently in use by a previous write operation.
The cancellation token was canceled. This exception is stored into the returned task.
You can create a cancellation token by creating an instance of the CancellationTokenSource class and passing the Token property as the cancellationToken
parameter.
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 Write(Byte[], Int32, Int32).
Product | Versions |
---|---|
.NET | Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9, 10 |
.NET Framework | 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1 |
.NET Standard | 1.5, 1.6, 2.0, 2.1 |
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