Programmatically set filename and path in Microsoft Print to PDF printer

As noted in other answers, you can force PrinterSettings.PrintToFile = true, and set the PrinterSettings.PrintFileName, but then your user doesn't get the save as popup. My solution is to go ahead and show the Save As dialog myself, populating that with my "suggested" filename [in my case, a text file (.txt) which I change to .pdf], then set the PrintFileName to the result.

DialogResult userResp = printDialog.ShowDialog();if (userResp == DialogResult.OK){    if (printDialog.PrinterSettings.PrinterName == "Microsoft Print to PDF")    {   // force a reasonable filename        string basename = Path.GetFileNameWithoutExtension(myFileName);        string directory = Path.GetDirectoryName(myFileName);        prtDoc.PrinterSettings.PrintToFile = true;        // confirm the user wants to use that name        SaveFileDialog pdfSaveDialog = new SaveFileDialog();        pdfSaveDialog.InitialDirectory = directory;        pdfSaveDialog.FileName = basename + ".pdf";        pdfSaveDialog.Filter = "PDF File|*.pdf";        userResp = pdfSaveDialog.ShowDialog();        if (userResp != DialogResult.Cancel)            prtDoc.PrinterSettings.PrintFileName = pdfSaveDialog.FileName;    }    if (userResp != DialogResult.Cancel)  // in case they canceled the save as dialog    {        prtDoc.Print();    }}

I did some experimenting myself but like yourself was also not able to prefill the SaveAs dialog in the PrintDialog with the DocumentName or PrinterSettings.PrintFileName already filled in the PrintDocument instance. This seems counterintuitive, so maybe I'm missing something

If you want to, you can however bypass the printdialog and print automatically without any user interaction at all. If you choose to do so, you must make sure beforehand that the directory to which you want to add a document to is in existence and that the document to be added is not in existence.

string existingPathName = @"C:\Users\UserName\Documents";string notExistingFileName = @"C:\Users\UserName\Documents\TestPrinting1.pdf";if (Directory.Exists(existingPathName) && !File.Exists(notExistingFileName)){    PrintDocument pdoc = new PrintDocument();    pdoc.PrinterSettings.PrinterName = "Microsoft Print to PDF";    pdoc.PrinterSettings.PrintFileName = notExistingFileName;    pdoc.PrinterSettings.PrintToFile = true;    pdoc.PrintPage += pdoc_PrintPage;    pdoc.Print(); }

It seems like the PrintFilename is ignored if the PrintToFile property is not set to true. If PrintToFile is set to true and a valid filename (full path) is provided, the filedialog where the user selects filename will not be displayed.

Tip: When setting the printername of the printersettings you can check the IsValid property to check that this printer actually exists. For more info on printersettings and finding installed printers check this post