Macro that Exports All Sheets to DWG

***UPDATED***
Code has been updated to fix a bug with Sheet Placeholders causing an error.

Jay Zallan asked me if I could help him create a macro that would quickly export all sheets to DWG files for his consultants that only use CAD. Here is the result, a macro that will export all the sheets to DWG into a dated subfolder where the model is located. The DWGs have bound views and shared coordinates.

Macro has also been added to https://bitbucket.org/BoostYourBIM/revit_api_public/

Code:
        public void ExportSheetsToDWG()
        {
            // setup uidoc and doc for accessing the Revit UI (uidoc) and the Model (doc)
            UIDocument uidoc = this.ActiveUIDocument;
            Document doc = uidoc.Document;
           
            // get all the elements in the model database
            FilteredElementCollector collector = new FilteredElementCollector(doc);
            // filter out all elements except Views
            ICollection<Element> collection = collector.OfClass(typeof(ViewSheet)).ToElements();
           
            // create a transaction
            using(Transaction t = new Transaction(doc, "Export Sheets"))
            {
                // start the transaction
                t.Start();
               
                // create a list to hold the sheets
                List<ElementId> sheetsToDWG = new List<ElementId>();
               
                // create DWG export options
                DWGExportOptions dwgOptions = new DWGExportOptions();
                dwgOptions.MergedViews = true;
                dwgOptions.SharedCoords = true;
               
                // add a counter to count the sheets exported
                int x = 0;
            
                // loop through each view in the model
                foreach (Element e in collection)
                {                   
                    try
                    {   
                        ViewSheet viewsheet = e as ViewSheet;
                       
                        // only add sheets to list
                        if (viewsheet.IsPlaceholder == false)
                        {
                            sheetsToDWG.Add(e.Id);
                            x += 1;
                        }
                    }
                    catch
                    {
                    }
                }

                string path = "";
                string file = "";
               
                // get the current date and time
                DateTime dtnow = DateTime.Now;
                string dt = string.Format("{0:yyyyMMdd HHmm}", dtnow);
               
                if (doc.PathName != "")
                {
                    // use model path + date and time
                    path = Path.GetDirectoryName(doc.PathName) + "\\" + dt;                   
                }
                else
                {
                    // model has not been saved
                    // use C:\DWG_Export + date and time
                    path = "C:\\DWG_Export\\" + dt;
                    file = "NONAME";
                }
               
                // create folder
                Directory.CreateDirectory(path);
               
                // export
                doc.Export(path, file, sheetsToDWG, dwgOptions);
               
                TaskDialog.Show("Export Sheets to DWG", x + " sheets exported to:\n" + path);
            }
        }