IFC Revit Native Family and Parameters

[Anonymous]

Hi,

I'm new in IFC File, can someone explain how is IFC works with Revit?

I'm trying to understand how Revit read/write data from/to IFC files as I can write IFC File that is readable by Revit. 

I tried to place two Revit native furniture desk into space, and export to IFC File.

Then I open the IFC File in Revit (without any modification to the IFC File), the Type Properties of the desk is LOST ?!

and the families and type in the project browser is changed too?

How can I retain these information for export and import IFC?

How can I map the Revit Family and Type Properties from IFC File?

Please Help... Thanks!