September 17, 2014
Working with ArcGIS data in combination with AutoLISP gives me flexible and powerful ways to edit data in AutoCAD that I can optimize and automate. The fact that that data is also in an Esri recognized GIS data format doesn't have to be the only reason to use ArcGIS for AutoCAD. The shear power of structured data in AutoCAD has many potential uses.
However ArcGIS for AutoCAD is primarily a tool to interoperate with ArcGIS data and the ArcGIS System. The AutoLISP API available with the ArcGIS for AutoCAD 350 release allows me to imagine and create useful ArcGIS data-building and data-manipulation tools. I have shared some of these in a growing collection of ArcGIS for AutoCAD bonus tools here free for download. These tools are documented in the include user's guide and demonstrated here on my YouTube GISCADChannel.
The bonus tool command, ESRI_LAYERTOFC will create local ArcGIS feature classes from every AutoCAD layer in your drawing according to the geometric types of entities found on each layer. It will name the feature classes based on the layer name and if needed distinguish between the different geometric types by appending a suffix name qualifier.
After downloading, loading and running the command you will have local feature classes created for each AutoCAD layer in your drawing that contains features of the various possible geometric types. If the AutoCAD layer contains entities all of the same geometric type then the command will just create a single feature class definition and the name of the feature class will be the name of the layer without any suffix name qualifier. It is likely you may have more feature classes than you wanted but there is no harm in removing the feature class definitions since removing feature class definitions has no effect on the entities themselves.
I use this tool on well structured drawings where the data was authored in such a way that each AutoCAD layer would equate well to a corresponding ArcGIS layer. At the time of writing this post, the current version of the ArcGIS for AutoCAD bonus tools is (1.3).