/// <summary>
/// Reads and removes a message from the queue. This method is thread-safe.
/// </summary>
/// <param name="readingDelegate">Custom delegate to read using message's stream.</param>
/// <param name="parameter">Delegate parameter object.</param>
/// <param name="timeout">Operation timeout.</param>
/// <returns>
/// ChannelStateOperationResult with ChannelState and OperationStatus.Completed, OperationStatus.QueueIsEmpty, OperationStatus.Timeout, OperationStatus.Cancelled,
/// OperationStatus.DelegateFailed, OperationStatus.RequestedLengthIsGreaterThanLogicalAddressSpace, OperationStatus.RequestedLengthIsGreaterThanVirtualAddressSpace,
/// or any OperationStatus returned by readingDelegate.
/// </returns>
public IAsyncOperation <ChannelStateOperationResult> ReadAsync(AsynchronousReadingDelegateWithParameterAndResult readingDelegate, object parameter, TimeSpan timeout)
{
return(AsyncInfo.Run(async cancellationToken =>
{
return new ChannelStateOperationResult(await _internal.ReadAsync(DelegateHelper.Wrap(readingDelegate), parameter, cancellationToken, timeout));
}));
}
public static Func <MemoryMappedViewStream, object, CancellationToken, Task <Internal.OperationStatus> > Wrap(AsynchronousReadingDelegateWithParameterAndResult externalDelegate)
{
return(async(MemoryMappedViewStream stream, object parameter, CancellationToken cancellationToken) =>
{
if (externalDelegate == null)
{
return Internal.OperationStatus.Completed;
}
var result = await externalDelegate.Invoke(stream.AsRandomAccessStream(), parameter).AsTask(cancellationToken);
return (Internal.OperationStatus)result;
});
}
