How to get TextureMapping data of an object

Questions about RhinoCommon:

I use code to add a BoxMapping to the object, when I use TextureMapping to get the Mapping, I can get the type of Mapping is BoxMapping, but I do not know how to get the BoxMapping’s box-data

Try this method:
TryGetMappingBox(out plane,out dx,out dy,out dz);

thank you