Topic: Rewriting program - opinions?

[T.Willey]

They seem to be about the same speed wise, but yours also purged out xref layers, while I make sure I don't.  Don't know if that matters or not, but I noticed it did on my little drawing, and a drawing that purged out 162 layers.

[T.Willey]

Glenn, whilst what you are saying makes sense in my head, Im not sure how to do that.  Can you give me a nudge in the right direction? 

Maybe something like this.

Code: [Select]

public ObjectIdCollection GetPurgableIds (Database db, ObjectId TabId) {
ObjectIdCollection idsToPurge = new ObjectIdCollection();
using (Transaction Trans = db.TransactionManager.StartTransaction()) {
SymbolTable SymTbl = Trans.GetObject(TabId, OpenMode.ForRead) as SymbolTable;
foreach (ObjectId ObjId in SymTbl) {
idsToPurge.Add(ObjId);
}
db.Purge(idsToPurge);
}
return idsToPurge;
}
Then called like

Code: [Select]

ObjectIdCollection PurgableIds = GetPurgableIds (Db, Db.LayerTableId);

Edit:  Show complete code to erase layers.
Edit3:  Made it show it won't try and erase items that are dependent on xrefs.  Shown in the code in red.

Code: [Select]

[CommandMethod("PC2")]
public void PurgeCurrentDocument2() {
Document Doc = acadApp.DocumentManager.MdiActiveDocument;
Database Db = Doc.Database;
Editor Ed = Doc.Editor;
using (Transaction Trans = Db.TransactionManager.StartTransaction()) {
ObjectIdCollection PurgeIds = GetPurgableIds(Db, Db.LayerTableId);
[color=red] int CountIds = PurgeIds.Count;[/color]
foreach (ObjectId ObjId in PurgeIds) {
SymbolTableRecord SymTblRec = Trans.GetObject(ObjId, OpenMode.ForWrite) as SymbolTableRecord;
[color=red] if (SymTblRec.IsDependent)
--CountIds;
else {
Ed.WriteMessage("\n Deleted layer: {0}", SymTblRec.Name);
SymTblRec.Erase();
}[/color]
}
[color=red] Ed.WriteMessage("\n {0} total number of layers deleted.", CountIds);[/color]
}
}

I learned something new.  Now to go read up on the Purge method. 

Edit2:  Glenn beat me to the punch.  See code below.  Thanks Glenn.

[Glenn R]

Tim,

Spot on, but you can also apply that to the foreach loop you would use to delete the id's as well.

Writing this in line off the top of my head without testing:

foreach (objectId symbolTableRecordId in SomeSymbolTable) {
  SymbolTableRecord symbolTableRecord = tr.Getobject(symbolTableRecordId, openMode.ForWrite, true) as SymbolTableRecord;
  symbolTableRecord.Erase();
}

Cheers,
Glenn.

[BeanBag]

T Willey I got your first program to work but seems to be a problem when using symboltablerecord.

Your program runs through and tells me its deleted the expected layers but the layers still exist.

It would seem this line is not doing what it should:

Code: [Select]

SymTblRec.Erase();
Using Express 2008 and Autocad 2008 - only learning  .Net for Cad right now so can't be much help.

[David Hall]

I am a little confused on this piece here.

Code: [Select]

using (Transaction Trans = Db.TransactionManager.StartTransaction())
        {
            ObjectIdCollection PurgeIds = GetPurgableIds(Db, Db.BlockTableId );
            //ObjectIdCollection PurgeIds = GetPurgableIds(Db, Db.LayerTableId);
            int CountIds = PurgeIds.Count;
            foreach (ObjectId ObjId in PurgeIds)
            {
                SymbolTableRecord SymTblRec = Trans.GetObject(ObjId, OpenMode.ForWrite) as SymbolTableRecord;
                if (SymTblRec.IsDependent)
                    --CountIds;
                else
                {
                    Ed.WriteMessage("\n Deleted block: {0}", SymTblRec.Name);
                    SymTblRec.Erase();
                }
            }
            Ed.WriteMessage("\n {0} total number of layers deleted.", CountIds);
        }
from Acad
Command: PC2
 Deleted block: 3D-TTL-A


I swapped the LayerTableId for BlockTableId.  As I step through the code, I see the SymTblRec.Erase() work, yet when its done, the block definition is not purged.  Any ideas?

[Kerry]

David, I haven't looked at the code, but ..

Are the blocks/layers still there if you save and re-open the drawing ?

As I understand it ;
The table entries are not actually erased, they are marked as 'to be erased' ( or somesuch ) and don't actually get removed till the drawing is closed. ... think about 'UNDO' capability. 

added:
They should not show in the blocks/layers dialog however ... they are still accessable if you iterate the table.

[David Hall]

I just tried, and its a no-go.  I wonder if the Layer/Block Table Ids have to be cast back to their "proper" Ids not generic SymbolTableId.  Ill try that next

[It's Alive!]

                SymbolTableRecord SymTblRec = Trans.GetObject(ObjId, OpenMode.ForWrite) as SymbolTableRecord;

this?

Code: [Select]

SymbolTableRecord SymTblRec = Trans.GetObject(ObjId, OpenMode.ForWrite,false) as SymbolTableRecord;


edit ...DoH Sorry I should have read the post

[T.Willey]

T Willey I got your first program to work but seems to be a problem when using symboltablerecord.

Your program runs through and tells me its deleted the expected layers but the layers still exist.

It would seem this line is not doing what it should:

Code: [Select]

SymTblRec.Erase();
Using Express 2008 and Autocad 2008 - only learning  .Net for Cad right now so can't be much help.

I am a little confused on this piece here.

Code: [Select]

using (Transaction Trans = Db.TransactionManager.StartTransaction())
        {
            ObjectIdCollection PurgeIds = GetPurgableIds(Db, Db.BlockTableId );
            //ObjectIdCollection PurgeIds = GetPurgableIds(Db, Db.LayerTableId);
            int CountIds = PurgeIds.Count;
            foreach (ObjectId ObjId in PurgeIds)
            {
                SymbolTableRecord SymTblRec = Trans.GetObject(ObjId, OpenMode.ForWrite) as SymbolTableRecord;
                if (SymTblRec.IsDependent)
                    --CountIds;
                else
                {
                    Ed.WriteMessage("\n Deleted block: {0}", SymTblRec.Name);
                    SymTblRec.Erase();
                }
            }
            Ed.WriteMessage("\n {0} total number of layers deleted.", CountIds);
        }
from Acad
Command: PC2
 Deleted block: 3D-TTL-A


I swapped the LayerTableId for BlockTableId.  As I step through the code, I see the SymTblRec.Erase() work, yet when its done, the block definition is not purged.  Any ideas?

That is because I forgot to 'commit' the transaction.  Sorry.     After the 'Ed.WriteMessage....' line add 'Trans.Commit()' and all should be fine again.   

[Kerry]

>>>>>>>>>>>>>  add 'Trans.Commit()' and all should be fine again.   

just came back to ask about that possibility

[David Hall]

DUH!!!!!!!!!!
I was so wrapped up in trying to switch to the BlockTable and LayerTable at same time, I didn't read all the way down, I just copied and pasted.

[David Hall]

That did it

[T.Willey]

That did it

Good to hear! 


ps.  BeanBag  Welcome to theSwamp.    I'm just starting with .Net also, and this is a great place to be to learn.

[T.Willey]

DUH!!!!!!!!!!
I was so wrapped up in trying to switch to the BlockTable and LayerTable at same time, I didn't read all the way down, I just copied and pasted.

On a side note, you might want to read the Arx doc's about the 'purge' method and the two ways in which it can be called.  It says that if you want to purge something that can reference something within the same table, ie. blocks, then you want to pass it something besides an ObjectIdCollection.

<snip>

purge(

AcDbObjectIdGraph& idGraph);

idGraph Input graph of objects in the database. The graph will be returned containing only those objects that may safely be removed from the database.

This version of the purge() method works in one pass. The method looks for references between the objects passed in so that it does not need to be called multiple times. In other words, if a Layer and a Linetype are passed in, and the only reference to the Linetype is from the Layer, then the graph returned will indicate that both the Layer and the Linetype can be purged. (The older AcDbObjectIdArray version of purge() would first indicate that only the Layer could be purged. Then a second call, after erasing the Layer, would say that the Linetype could be purged.)

<snip>