IAcSmFileReference

The Sheet ObjectId interface (reference to file object).

available methods :

(setq cad (vlax-get-acad-object))
(setq doc (vla-get-ActiveDocument cad))
(setq ssmgr (vla-GetInterfaceObject cad "BricscadSm.AcSmSheetSetMgr"))
(setq smdb (vlax-invoke-method ssmgr 'OpenDatabase dstfile))
(setq sheetset (vlax-invoke-method smdb 'GetSheetSet))
(setq fileref (vlax-invoke-method sheetset "GetNewSheetLocation"))

SetFileName	assigns the filename that this object will reference (vlax-invoke-method fileref 'SetFileName "not_existing_file.dat") HRESULT SetFileName ([in] BSTR pFilename)
GetFileName	returns the filename of this file reference (setq name (vlax-invoke-method fileref 'GetFileName)) HRESULT GetFileName ([out, retval] BSTR* ppFilename)
ResolveFileName	resolves the referenced file as fully qualified filename (setq res (vlax-invoke-method fileref 'ResolveFileName)) HRESULT ResolveFileName ([out, retval] BSTR* pFilenamet)