How to add new objects to a exist blocktablerecord?

[swaywood]

Hi everyone,

I want to clear all objects in an existing blocktablerecord,

add several new objects, and redefine the block.

I wrote some code according to my own ideas,

but the new block generated is an empty block.

Please help me find out what the problem is.

Thank you

    public static ObjectId AddBlockTableRecord(this Database db, string blockName, Point3d Position, params ObjectId[] ids)
    {
      BlockTable bt = (BlockTable)db.BlockTableId.GetObject(OpenMode.ForRead);
      BlockTableRecord btr;
      using (Transaction trans = db.TransactionManager.StartTransaction())
      {
        if (!bt.Has(blockName)) 
        {
          btr = new BlockTableRecord();
          btr.Name = blockName;
        }
        else
        {
          btr = (BlockTableRecord)trans.GetObject(bt[blockName], OpenMode.ForWrite);
          foreach (ObjectId id in btr)
          {
            Entity ent = (Entity)trans.GetObject(id, OpenMode.ForWrite);
            ent.Erase();
          }
        }
        btr.Explodable = true;
        btr.Origin = Position;

        foreach (ObjectId id in ids)
        {
          Entity ent = id.Clone<Entity>();
          if (ent.IsNewObject)
          {
            btr.AppendEntity(ent);
          }
        }
        bt.UpgradeOpen();
        if (!bt.Has(blockName))
        {
          bt.Add(btr);
          db.TransactionManager.AddNewlyCreatedDBObject(btr, true);
        }
        else
        {

        }
        foreach (ObjectId id in ids)
        {
          if (!id.IsNull)
          {
            id.GetObject(OpenMode.ForWrite).Erase(true);
          }
        }
        btr.DowngradeOpen();
        bt.DowngradeOpen();
        trans.Commit();
      }
      return bt[blockName];
    }

[_gile · Accepted solution]

Hi,

You should use the Database.DeepCloneObject method instead of the RXObjectClone one.

IMO, it's also better to move the entities within the block definition instead of defining the BlockTableRecord.Origin property.

And also, you should either strart a new transaction or use the TopTransaction, but not mix both.

public static ObjectId AddBlockTableRecord(this Database db, string blockName, Point3d Position, params ObjectId[] ids)
        {
            ObjectId btrId;
            BlockTableRecord btr;
            using (Transaction trans = db.TransactionManager.StartTransaction())
            {
                var bt = (BlockTable)trans.GetObject(db.BlockTableId, OpenMode.ForRead);
                if (!bt.Has(blockName))
                {
                    btr = new BlockTableRecord();
                    btr.Name = blockName;
                    trans.GetObject(db.BlockTableId, OpenMode.ForWrite);
                    btrId = bt.Add(btr);
                    trans.AddNewlyCreatedDBObject(btr, true);
                }
                else
                {
                    btrId = bt[blockName];
                    btr = (BlockTableRecord)trans.GetObject(btrId, OpenMode.ForWrite);
                    foreach (ObjectId id in btr)
                    {
                        trans.GetObject(id, OpenMode.ForWrite).Erase();
                    }
                }
                btr.Explodable = true;

                var oIds = new ObjectIdCollection(ids);
                var mapping = new IdMapping();
                db.DeepCloneObjects(oIds, btrId, mapping, false);
                var displacement = Matrix3d.Displacement(Position.GetAsVector().Negate());
                foreach (IdPair pair in mapping)
                {
                    if (pair.IsCloned && pair.IsPrimary)
                    {
                        var entity = (Entity)trans.GetObject(pair.Value, OpenMode.ForWrite);
                        entity.TransformBy(displacement);
                    }
                }

                foreach (ObjectId id in ids)
                {
                    if (!id.IsNull)
                    {
                        id.GetObject(OpenMode.ForWrite).Erase(true);
                    }
                }
                trans.Commit();
            }
            return btrId;
        }

[swaywood]

thanks Giles