cancel checkInvariant close dump elementNameParse extensionsAdd extensionsCount extensionsLookupPrefix extensionsLookupUri extensionsPrefix extensionsUri fileName ImageFile isElementNameExtended isOpen isWritable operator!= operator== readerCount root writerCount

size_t extensionsCount ( ) const Get number of E57 extensions declared in the ImageFile. The default E57 namespace does not count as an extension. Precondition: This ImageFile must be open (i.e. isOpen()). Postcondition: No visible state is modified. Returns: The number of E57 extensions defined in the ImageFile. Exceptions: E57_ERROR_IMAGEFILE_NOT_OPEN E57_ERROR_INTERNAL All objects in undocumented state See also: Extensions.cpp example, ImageFile::extensionsPrefix, ImageFile::extensionsUri