Extract all the external links that have a CAD file

Question

Is there any way to extract all the external links files that have a CAD file?

Any library in c# or another programming language? Thanks in advance.

Answer 1

Ad hoc sample would be:

ObjectIdCollection XRefs = new ObjectIdCollection();

Database db = HostApplicationServices.WorkingDatabase;
using (Transaction tr = db.TransactionManager.StartTransaction())
{
    BlockTable blocks = tr.GetObject(db.BlockTableId, OpenMode.ForRead, false) as BlockTable;
    foreach (ObjectId blockId in blocks)
    {
        BlockTableRecord bx = tr.GetObject(blockId, OpenMode.ForRead, false) as BlockTableRecord;
        if (bx.IsFromExternalReference)
        {
            ObjectIdCollection references = bx.GetBlockReferenceIds(true, true);
            foreach (ObjectId ref in references)
            XRefs.Add (ref)
        }
    }
    tr.Dispose()
}