I posted this to my G+ circles, and we had a pretty active discussion, but no solution.
Back in the day, DWG TrueConnect added the Windows attributes of DWG Creator Name and DWG Creator Version. This worked fine in XP, but there doesn't appear to be a replacement for Win 7. Seth Hall, Being Civil contributor wrote about it here: http://beingcivil.typepad.com/my_weblog/2009/02/wh
In Win 7, you can show the DWG version, but not the Civil 3D version. Since the objects aren't backwards compatible and many offices run multiple versions of Civil 3D, it's important to open the drawing in the version in which it was created. Has anyone out there written a tool that will show the Civil 3D version? JTB World proposed an app that would populate a custom field, but that would only populate the field when the drawing was opened, you could then see the version, and that would be with the version you open it with (which may not be correct). There was no ability to see any information about files that hadn't been opened with the add-on.
I see in the dwg header, opened with notepad, that there are AC# associated with the drawing, but I don't think it has anything to do with the Civil 3D version. There's got to be some coding somewhere.
The data can be read in the dwg file, Lisa. I'm not quite sure how it can be used to show it in Explorer though. For anyone else that may want to look into this, each drawing has this information stored like so, with all characters separated by a space:
r e g i s t r y _ v e r s i o n = \ " 1 8 . 0 \ " i n s t a l l _ i d _ s t r i n g = \ " A C A D - 8 0 0 0 : 4 0 9 \ "
This is showing this drawing was last saved by version 18.0 (2010) by the product ACAD-8000 (C3D2010).
r e g i s t r y _ v e r s i o n = \ " 1 9 . 0 \ " i n s t a l l _ i d _ s t r i n g = \ " A C A D - B 0 0 0 : 4 0 9 \ "
This one was saved by version 19.0 (2013) by the product ACAD-B000 (C3D2013).
All Autocad based products have the code of ACAD-XXXX, I happen to know that those with X000 are C3D and the X changes with each version (9000 was 2011, A000 was 2012). There is a list available somewhere that shows all of the different product codes, but a quick search just now didn't locate it....I know it exists because I've used it in the past. (I know, I should've saved a copy locally.)
I see that in the file. I think I see the pattern:
18.0 = C3D 2010
18.1 = C3D 2011
18.2 = C3D 2012, all three are drawing version 2010
19.0 = C3D 2013 drawing version 2013
I'd assume that previous versions followed the same system, to a point.
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