Is a Civil 3D instance?

By Augusto Goncalves

This is a .NET version of the code posted by a colleague, see original here, redesigned to Civil 3D naming.

When we get a running instance of AutoCAD, we don’t know which vertical is actually running as all of them are basically the same root object. To determine which version we have, we need to try. And that’s what this code is doing.

' get the running instance of AutoCAD (or any vertical)
Dim acadApp As Object = GetObject(, "Autocad.Application")
' is it a Civil 3D? let's try!
Dim civilLandApp As Object
Try
  ' the 10.4 stands for 2015 release
  civilLandApp = acadApp.GetInterfaceObject
                 ("AeccXUiLand.AeccApplication.10.4")
Catch ex As Exception
  Return ' not Civil 3D
End Try
 
' now we know is Civil 3D
' do something

And in C# it’s basically the same, except that you need to decide whenever to use var or dynamic. The above code uses Object, that enables late-binding. If that is your option, then use the C# equivalent: dynamic