Civil 3D .NET API has FeatureLine class, but not many functionalities are exposed in the current release (Civil 3D 2013). On the other hand Civil 3D COM API has AeccLandFeatureLine Object and it has some useful functions exposed. I am aware, some of our Civil 3D application developers want to access the Land FeatureLine Vertices and in the absence of equivalent .NET API, I would suggest to use COM API IAeccLandFeatureLine:: GetPoints()
Here is a VB.NET code snippet which demonstrates how to get the Civil 3D Land FeatureLine Vertices –
Dim idEnt As ObjectId = promptEntRs.ObjectId
Dim ent As Autodesk.AutoCAD.DatabaseServices.Entity = DirectCast(trans.GetObject(idEnt, OpenMode.ForWrite), Autodesk.AutoCAD.DatabaseServices.Entity)
Dim oFtrLn As AeccLandFeatureLine = DirectCast(ent.AcadObject, Autodesk.AECC.Interop.Land.AeccLandFeatureLine)
Dim output As String = ""
Dim points() As Double = oFtrLn.GetPoints()
Dim varArraySurfacePoints As Object = oFtrLn.GetPoints()
Dim iPvertices As Long
For iPvertices = 0 To (oFtrLn.PointsCount * 3 - 1)
output = output & "Coordinate Values : " & points(iPvertices) & vbCrLf & vbLf
Next
ed.WriteMessage(vbCrLf + "Vertices of Selected Land Feature Line : ")
ed.WriteMessage(vbCrLf + output)
