area of a selected object vb.net

[dan_g8]

this is probably a very easy question, but how do you get the area of an polygon? i have created a polyline and selected it via

 

Dim acSSPrompt As PromptSelectionResult = acDoc.Editor.SelectLast()

 

ive spent ages on google looking to find how to do the simple task of reading the area but cant find how to do it! anyone got any pointers? vb.net is the script.

[BlackBox]

You iterate the SelctionSet's ObjectIds, opening the ObjectId as Polyline via Database Transaction, and cull the Area Property.

 

Cheers

Edited September 8, 2015 by BlackBox

[BlackBox]

You iterate the SelctionSet's ObjectIds, opening the ObjectId as Polyline via Database Transaction, and cull the Area Property.

 

Example (C#):

//<snip>
       private static void FOO()
       {
           Document doc = acDocs.MdiActiveDocument;
           Database db = doc.Database;
           Editor ed = doc.Editor;

           try
           {
               PromptSelectionResult psr = ed.SelectLast();

               if (psr.Status != PromptStatus.OK)
                   return;

               SelectionSet ss = psr.Value;
               ObjectId id = ss.GetObjectIds()[0];

               using (Transaction tr =
                       db.TransactionManager.StartOpenCloseTransaction())
               {
                   Polyline polyline = tr.GetObject(id, OpenMode.ForRead) as Polyline;

                   if (polyline != null)
                   {
                       ed.WriteMessage("\nPolyline Area: {0} \n", polyline.Area.ToString());
                   }
                   else
                   {
                       ed.WriteMessage("\n** Last object is not a Polyline. \n");
                   }                    

                   tr.Commit();
               }
           }
           catch (System.Exception ex)
           {
               ed.WriteMessage("\n; error: System.Exception: " + ex.Message);
           }
       }
//<snip>