CryptoStream.ReadAsync Method (Byte, Int32, Int32, CancellationToken)
Reads a sequence of bytes from the current stream asynchronously, advances the position within the stream by the number of bytes read, and monitors cancellation requests.
Assembly: mscorlib (in mscorlib.dll)
abstract ReadAsync : buffer:byte * offset:int * count:int * cancellationToken:CancellationToken -> Task<int> override ReadAsync : buffer:byte * offset:int * count:int * cancellationToken:CancellationToken -> Task<int>
- Type: System.Byte
The buffer to write the data into.
- Type: System.Int32
The byte offset in buffer at which to begin writing data from the stream.
- Type: System.Int32
The maximum number of bytes to read.
Return ValueType: System.Threading.Tasks.Task(Int32)
A task that represents the asynchronous read operation. The value of the task object's TResult parameter contains the total number of bytes read into the buffer. The result can be less than the number of bytes requested if the number of bytes currently available is less than the requested number, or it can be 0 (zero) if the end of the stream has been reached.
buffer is a null reference (Nothing in Visual Basic).
offset or count is negative.
The sum of offset and count is larger than the buffer length.
The stream does not support reading.
The stream has been disposed.
The stream is currently in use by a previous read operation.
You must preface your call to ReadAsync with the await (C#) or Await (Visual Basic) operator to suspend execution of the method until the task is complete. For more information, see Asynchronous Programming with Async and Await (C# and Visual Basic).
Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.