Вопрос SelectCrossingWindow DOTNET

  Dim ppo As New PromptPointOptions(vbLf & "Pick a Point: ")
                    Dim ppr As PromptPointResult
                    ppr = ed.GetPoint(ppo)
                    If ppr.Status <> PromptStatus.OK Then
                        ed.WriteMessage(vbCrLf & "wrong point specification!")
                        Exit Sub
                    End If
                    Dim p As Point3d = ppr.Value
                    '------------------------------------------------------------''
                    Dim vd As Vector3d = New Vector3d(1e-4, 1e-4, 1e-4) '<--  dicrease a fuzz to suit
                    Dim pMin As Point3d = p - vd
                    Dim pMax As Point3d = p + vd              
                    Dim tvs() As TypedValue = New TypedValue() { New TypedValue(0, "line")} '<--  измени тип объекта здесь
                    Dim points As Point3dCollection = New Point3dCollection
                    points.Add(pMin)
                    points.Add(pMax)
                    Dim sf As SelectionFilter = New SelectionFilter(tvs)
                    Dim sres As PromptSelectionResult = ed.SelectFence(points, sf)
                    If sres.Status <> PromptStatus.OK Then
                        ed.WriteMessage("\nWrong selection!")
                        Return
                    End If

                    If sres.Value.Count = 0 Then
                        ed.WriteMessage("\nNothing selected!")
                        Return
                    End If
                    '' cast entity as Line
                    Dim eid As ObjectId = sres.Value.GetObjectIds(0)
                    Dim ent As Entity = TryCast(tr.GetObject(eid, OpenMode.ForRead), Entity)
                    ''-----------------------------------------------------------''
                    Dim ln As Line = TryCast(ent, Line)
                    If ln IsNot Nothing Then
                        ed.WriteMessage(vbLf + "{0},{1},{2}", ln.StartPoint.X, ln.StartPoint.Y, ln.StartPoint.Z)
                    End If