Programmatically refresh layer usage information .NET

[Anonymous]

In C# I noticed that when I loop through the LayerTableRecords in the LayerTable some of the layers in the drawing do not show up.  If I look at the layers in the UI it shows the missing layers with a grey icon for their status while the ones that it does detect have a blue icon for their status.  The status has to do with which layers that the drawing believes are in use.  In the UI you can press a refresh button and this will fix the problem.  I want to know how I can fix this through the .NET API, COM API, or command line.

[Anonymous]

Have not tested it but have you tried the LayerTable method GenerateUsageData

[Anonymous]

I tried calling GenerateUsageData before doing a foreach loop on the LayerTable but it still didn't return all the layers.

[Anonymous]

Another thing that I noticed is that this problem only occurs when I open the database using Database.ReadDwgFile.  If I first open the drawing using Application.DocumentManager.Open and then get the database from MdiActiveDocument then all of the layers show up correctly.  I would open the drawing but it is much faster to alter the database.  All that I'm doing is setting Freeze/On/Locked on the layers.

[Anonymous]

Can you post your code that would help alot for helping you out.

[Anonymous]

The following shows two examples of enumerating through the layers.  The second option will work, but I as I said earlier I do not want to open the drawing.

Here's the code for just opening the database:

using (Database database = new Database(false, true))
        {
          database.ReadDwgFile(drawingFilePath, FileShare.ReadWrite, true, String.Empty);

          using (Transaction transaction = database.TransactionManager.StartTransaction())
          {
            LayerTable layerTable = transaction.GetObject(database.LayerTableId, OpenMode.ForWrite) as LayerTable;
            database.Clayer = database.LayerZero;
            
            foreach (ObjectId layerID in layerTable)
            {
              LayerTableRecord layer = (LayerTableRecord)transaction.GetObject(layerID, OpenMode.ForWrite);

              //Do something to layer
            }

            transaction.Commit();
          }
        }

Here's the code when opening the drawing:

Application.DocumentManager.Open(drawingFilePath, false);

      Document document = Application.DocumentManager.MdiActiveDocument;
      Database database = document.Database;
      DocumentLock documentLock = document.LockDocument(DocumentLockMode.Write, null, null, true);

      using (documentLock)
      {
        using (Transaction transaction = database.TransactionManager.StartTransaction())
        {
          LayerTable layerTable = transaction.GetObject(database.LayerTableId, OpenMode.ForWrite) as LayerTable;

          database.Clayer = database.LayerZero;

          foreach (ObjectId layerID in layerTable)
          {
            LayerTableRecord layer = (LayerTableRecord)transaction.GetObject(layerID, OpenMode.ForWrite);

            //Do something to layer
          }
        }
      }

[Anonymous · Accepted solution]

It seems that the problem was that one of the entities in the particular drawing was corrupt. When one of the users recreated the drawing (including re-adding some xrefs) and ran the program it worked just fine. I also double checked the code and it was definitely hitting the correct layers this time. I am however open to suggestions or solutions on how to detect corruption problems in AutoCAD drawings.

[harryliu3140]

Exactly the same issue hasn't been solved in ACAD2012. I tried to Audit and recover my dwg file and found nothing corrupted. How many years needed to solve it?