Determines if the specified curve is closed (that is, the start point is the same as the endpoint)
The VLA-object to be tested.
T if the curve is closed; otherwise nil.
is closed:Determine if the ellipse used to demonstrate
_$ (vlax-curve-isClosed ellipseObj)
is closed:Determine if the spline used to demonstrate
_$ (vlax-curve-isClosed splineObj)