Finding the group name to which entity belongs

csharp

Finding the group name to which entity belongsBy Virupaksha Aithal
Groups are stored as persistent reactors in the AutoCAD entity so, “DbObject::GetPersistentReactorIds” API can be used to identify the group associated with AutoCAD entity. Below code shows the procedure to use “GetPersistentReactorIds” to identify the group’s to which a selected entity is belongs.

[CommandMethod("FindGroup")]

static public void FindGroup()

{

    Document doc =

        Application.DocumentManager.MdiActiveDocument;

    Database db = doc.Database;

    Editor ed = doc.Editor;

    PromptEntityResult acSSPrompt =

        ed.GetEntity("Select the entity to find the group");

    if (acSSPrompt.Status != PromptStatus.OK)

        return;

    using (Transaction Tx =

        db.TransactionManager.StartTransaction())

    {

        Entity ent = Tx.GetObject(acSSPrompt.ObjectId,

                                OpenMode.ForRead) as Entity;

        ObjectIdCollection ids = ent.GetPersistentReactorIds();

        bool bPartOfGroup = false;

        foreach (ObjectId id in ids)

        {

            DBObject obj = Tx.GetObject(id, OpenMode.ForRead);

            if (obj is Group)

            {

                Group group = obj as Group;

                bPartOfGroup = true;

                ed.WriteMessage(

                    "Entity is part of " + group.Name + " group\n");

            }

        }

        if(!bPartOfGroup)

            ed.WriteMessage(

                   "Entity is Not part of any group\n");

        Tx.Commit();

    }

}