vb.net how to close a polyline?

[shirazbj]

Hi,

 

I want calculate the area of a closed polyline. I pick up a polyline and If it is not closed, I want to close it. But the code below doesn't work.

 

                            If lwpoly.Closed = False Then
                               lwpoly.Closed = True
                           End If

 

It returns an internal error saying "eNotOpenForWrite". Just wondering how should I close a polyline with vb.net 2008 express for autocad 2010.

 

Thanks in advance

 

Cean

[Jeff H]

Looks like you opened it for read so try

 

           If lwpoly.Closed = False Then
               lwpoly.UpgradeOpen()
               lwpoly.Closed = True
           End If

[shirazbj]

Thanks Jeff, It works.

 

I was playing with a code from theswamp - .net polyline routines

It has one line like this:

 

Dim obj As DBObject = tr.GetObject(res.ObjectId, OpenMode.ForRead)

 

I think I should change here.