Using Programming Languages other than VBA

Sub Example_IsPlanar()
   ' This example creates a Spline object in model space and
   ' determines whether the Spline is planar

	Dim splineObj As AcadSpline
	Dim startTan(0 To 2) As Double, endTan(0 To 2) As Double
	Dim fitPoints(0 To 8) As Double
	Dim UserMessage As String

	' Define the Spline object
	startTan(0) = 0.5: startTan(1) = 0.5: startTan(2) = 0
	endTan(0) = 0.5: endTan(1) = 0.5: endTan(2) = 0
	fitPoints(0) = 0: fitPoints(1) = 0: fitPoints(2) = 0: fitPoints(3) = 5
	fitPoints(4) = 5: fitPoints(5) = 0: fitPoints(6) = 10: fitPoints(7) = 0: fitPoints(8) = 0

	' Create new Spline object
	Set splineObj = ThisDrawing.ModelSpace.AddSpline(fitPoints, startTan, endTan)
	ThisDrawing.Application.ZoomAll

	' Display whether or not new Spline is planar
	UserMessage = IIf(splineObj.IsPlanar, "is planar", "is not planar")

	MsgBox "The new Spline " & UserMessage

End Sub