Despite the option to "merge layers" in the AI DXF import dialog, I find that in fact when I import a DXF it all ends up in a single layer (whether that option is ticked or not).
The DXF comes from the British government "Ordnance Survey" mapping agency. It has several dozen layers in it.
Each layer has its own Autocad color number (dxf group code 62) and AI correctly notices this and assigns the right colour to each object. But it always merges the layers.
Any fix for this?
If you are using CS3, they had a problem with everything going to one layer.
http://helpx.adobe.com/illustrator/kb/updated-dfx-dwg-plug-illustrator .html
If not CS3, what version are you using?
You'll probably have to recreate the layers. If infact everything is color coded then it is simply a matter of choosing everything with a given color and placing it on a new layer. Use the Select Same Fill/Stroke (as appropriate) and just drag the little square at the right end of the layer line to the new layer. It will probably help to turn off the visibility of the layer as you complete each just to keep track.
Thanks. Yes I could do that, but was really hoping Adobe might come up with a DXF import that actually works correctly. After all, if they put a tick box purportedly allowing you to choose whether or not to "merge layers" then it should work.
I tried the solution suggested by ru73 above. That is a revised plug-in for CS3 which is supposed to preserve Autocad layers and does not have the tick box (so I guess it's earlier). It ran ok within AI CS5.1 but didn't solve the problem.
Actually you can download the whole map for the UK free, but its 150 MB. I've put up on my web site a small tile of it:-
http://www.brisk.org.uk/pics/su42.dxf
This data is copyright the Ordnance Survey and please respect it is just for test purposes here.
I also tried importing this into CorelDraw. That preserves all the layers perfectly. However, it has other serious problems. So at the moment I'm stymied in both directions. The layer names are seen in this screen clip of CorelDraw:
I've finally solved this. It depends how you import it. If you OPEN the DXF it keeps the layers. If you create a blank new document and then PLACE the DXF, it doesn't. With the benefit of hindsight, I supose that's obvious enough, since placing involves having some layer activated. Thanks for the help.
North America
Europe, Middle East and Africa
Asia Pacific