public static void MagicReplaceCommand() { // objects initializing var nomutt = Convert.ToInt32(Autodesk.AutoCAD.ApplicationServices.Core.Application.GetSystemVariable("nomutt")); var doc = Autodesk.AutoCAD.ApplicationServices.Core.Application.DocumentManager.MdiActiveDocument; var ed = doc.Editor; var db = doc.Database; try { using (doc.LockDocument()) { using (var tr = new QuickTransaction()) { var toreplace = tr.GetImpliedOrSelect(new PromptSelectionOptions()); if (toreplace == null) { return; } ed.WriteMessage("\nSelect destinion block: "); var totype = Quick.SelectSingle(); ed.WriteMessage("\n"); if (totype == null) { return; } var masterblock = (BlockTableRecord)tr.GetObject(((BlockReference)tr.GetObject(totype ?? ObjectId.Null, OpenMode.ForWrite)).BlockTableRecord, OpenMode.ForRead); var bt = tr.GetObject(db.BlockTableId, OpenMode.ForRead) as BlockTable; var @new = bt[masterblock.Name]; Autodesk.AutoCAD.ApplicationServices.Core.Application.SetSystemVariable("nomutt", 0); var notparsed = 0; var flattern = false; var objs = toreplace.Cast <SelectedObject>().Select(o => tr.GetObject(o.ObjectId, OpenMode.ForRead) as Entity).ToArray(); if (objs.Any(o => (o as BlockReference)?.Position.Z > 0)) { flattern = Quick.AskQuestion("Should flattern blocks with Z value", true) ?? false; } var os = new List <ObjectId>(); foreach (var ent in objs) { var oldblk = ent as BlockReference; if (oldblk == null) { //not block.. notparsed++; continue; } var p = oldblk.Position; var ip = flattern ? new Point3d(p.X, p.Y, 0) : p; var scl = oldblk.ScaleFactors; var rot = oldblk.Rotation; var newblk = new BlockReference(ip, @new); newblk.SetPropertiesFrom(ent); newblk.Rotation = rot; newblk.ScaleFactors = scl; tr.BlockTableRecordCurrentSpace.AppendEntity(newblk); tr.AddNewlyCreatedDBObject(newblk, true); ApplyAttributes(db, tr, newblk); oldblk.UpgradeOpen(); oldblk.Erase(); oldblk.Dispose(); os.Add(newblk.ObjectId); } Autodesk.AutoCAD.ApplicationServices.Core.Application.SetSystemVariable("nomutt", 1); tr.Commit(); if (notparsed > 0) { ed.WriteMessage($"{notparsed} are not blocks and were not replaced.\n"); } ed.WriteMessage($"{toreplace.Count} were replaced to block {masterblock.Name} successfully.\n"); Quick.SetSelected(os.ToArray()); } } } catch (Exception ex) { ed.WriteMessage(ex.Message + "\n" + ex.StackTrace); } finally { Autodesk.AutoCAD.ApplicationServices.Core.Application.SetSystemVariable("nomutt", nomutt); } }