.NET

[#1]

I want to get all names of layers in a drawing ,and then  put them in a array.  how to carry out it.

[#2]

I think easier to gather layer names to List of string

then you can easy to convert to array using

List.ToArray() method

Here is a quick sample:

// This method can have any name
        [CommandMethod("DisplayLayers","displa", CommandFlags.Modal)]
        public void TestDisplayLayers()
        {
            Document doc = Autodesk.AutoCAD.ApplicationServices.Application.DocumentManager.MdiActiveDocument;
            Database db = doc.Database;
            Editor ed = doc.Editor;
            List<string> info = LayersToList(db);
            foreach (string lname in info)
                ed.WriteMessage("\nLayer Name: \t{0}", lname);

        }

        public List<string> LayersToList(Database db)
        {
            List<string> lstlay = new List<string>();

            LayerTableRecord layer;
            using (Transaction tr = db.TransactionManager.StartOpenCloseTransaction())
            {
                LayerTable lt = tr.GetObject(db.LayerTableId, OpenMode.ForRead) as LayerTable;
                foreach (ObjectId layerId in lt)
                {
                    layer = tr.GetObject (layerId, OpenMode.ForWrite) as LayerTableRecord;
                    lstlay.Add(layer.Name);
                }

            }
            return lstlay;
        }

~'J'~

[#3]

Just curious Hallex, what's different about "StartOpenCloseTransaction" as opposed to "StartTransaction"?

[#4]

To be honestly I did not read Arx docs about this

I use it when I just do nothing in the drawing,

as in this case to read something from document only