Referencing the LayerStateManager

Arno Van Eeuwen

In VBA for V11 I can use 

 Dim lstManger As AcadLayerStateManager

 Set lstManger = ThisDrawing.Application.GetInterfaceObject("BricscadApp.AcadLayerStateManager")

what is the equivalent for COM in C#?

 

TIA

Arno van Eeuwen