Hello Vinitha,
The situation indeed seems to be how you mentioned, with the .NET assembly not exposing any controls. However there are quiet a few API available with NI-Digital pattern Driver to program using LabVIEW. Now I cannot be sure if using them would actually meet your requirements.
A little background on what you are trying to achieve and why you think .NET containers can help would be useful in getting to a practical solution.
Regards
Ashwin