MemoryStream.CopyToAsync(Stream, Int32, CancellationToken) Method

Definition

Asynchronously reads all the bytes from the current stream and writes them to another stream, using a specified buffer size and cancellation token.

public override System.Threading.Tasks.Task CopyToAsync (System.IO.Stream destination, int bufferSize, System.Threading.CancellationToken cancellationToken);

Parameters

destination
Stream

The stream to which the contents of the current stream will be copied.

bufferSize
Int32

The size, in bytes, of the buffer. This value must be greater than zero.

cancellationToken
CancellationToken

The token to monitor for cancellation requests.

Returns

A task that represents the asynchronous copy operation.

Exceptions

destination is null.

buffersize is negative or zero.

Either the current stream or the destination stream is disposed.

The current stream does not support reading, or the destination stream does not support writing.

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

Remarks

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 CopyTo(Stream, Int32).

Applies to

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
.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 1.3, 1.4, 1.5, 1.6, 2.0, 2.1
UWP 10.0