Purge CAD

PurgeCAD.cs

public static void PurgesCAD()
        {
            Document doc = Autodesk.AutoCAD.ApplicationServices.Core.Application.DocumentManager.MdiActiveDocument;
            Database db = doc.Database;
            using (Transaction Tx = db.TransactionManager.StartTransaction())
            {
                BlockTable table = Tx.GetObject(db.BlockTableId,
                    OpenMode.ForRead) as BlockTable;
                ObjectIdCollection blockIds = new ObjectIdCollection();
                do
                {
                    blockIds.Clear();
                    foreach (ObjectId id in table)
                        blockIds.Add(id);
                    db.Purge(blockIds);
                    foreach (ObjectId id in blockIds)
                    {
                        DBObject obj = Tx.GetObject(id, OpenMode.ForWrite);
                        obj.Erase();
                    }
                }
                while (blockIds.Count != 0);
                Tx.Commit();
            }