public void RebarToSolid()
		{
			UIDocument uidoc = this.ActiveUIDocument;
			Document doc = uidoc.Document;
			
			ICollection<Element> rebers = new FilteredElementCollector(doc, doc.ActiveView.Id).OfCategory(BuiltInCategory.OST_Rebar).ToElements();
                List<Rebar> List_Rebar = new List<Rebar>();
                if(rebers==null)
                {
                    TaskDialog.Show("REBAR", "NO REBAR EXISTS IN THE DRAWINGS");
                } 
                Transaction trans = new Transaction(doc);
                trans.Start("ACTRAN");
                IEnumerable<ViewFamilyType> VFT = from Element in new FilteredElementCollector(doc).OfClass(typeof(ViewFamilyType)) let type = Element as ViewFamilyType where type.ViewFamily == ViewFamily.ThreeDimensional select type;
                View3D v3d = doc.ActiveView as View3D;
               foreach(Rebar r in rebers)
                {
                    r.SetSolidInView(v3d, true);
                    List_Rebar.Add(r);
                }

                trans.Commit();
		}