I'm porting some custom .NET streams to WINRT. Language is C#. 

Is there some example implementation of IAsyncOperationWithProgress? Since Methods ReadAsync, WriteAsync from Windows.Storage.Streams require them. Custom WinRT streams implementations are welcomed also.

I found some C examples using create\_async, but i'm looking to do this in C#, and i cannot find create\_async in the Metro framework.

Thanks in advance