Reading printer settings from registry from DEVMODE structure?

Question

Windows

Good time of the day!
It is necessary to read the DEVMODE structure of the printer from the registry. Then change and write back.
Something does not work as it should, in the read structure of the beleberd there is some kind of information and not information about the printer.
I use the following code:

............
using System.Runtime.InteropServices;
............
        // DEVMODE structure
        [Flags()]
        enum DM : int
        {
            Orientation = 0x1,
            PaperSize = 0x2,
            PaperLength = 0x4,
            PaperWidth = 0x8,
            Scale = 0x10,
            Position = 0x20,
            NUP = 0x40,
            DisplayOrientation = 0x80,
            Copies = 0x100,
            DefaultSource = 0x200,
            PrintQuality = 0x400,
            Color = 0x800,
            Duplex = 0x1000,
            YResolution = 0x2000,
            TTOption = 0x4000,
            Collate = 0x8000,
            FormName = 0x10000,
            LogPixels = 0x20000,
            BitsPerPixel = 0x40000,
            PelsWidth = 0x80000,
            PelsHeight = 0x100000,
            DisplayFlags = 0x200000,
            DisplayFrequency = 0x400000,
            ICMMethod = 0x800000,
            ICMIntent = 0x1000000,
            MediaType = 0x2000000,
            DitherType = 0x4000000,
            PanningWidth = 0x8000000,
            PanningHeight = 0x10000000,
            DisplayFixedOutput = 0x20000000
        }
        struct POINTL
        {
            public Int32 x;
            public Int32 y;
        }
        
        [StructLayout(LayoutKind.Explicit, CharSet = CharSet.Ansi)]
        struct DEVMODE
        {
            public const int CCHDEVICENAME = 32;
            public const int CCHFORMNAME = 32;

            [MarshalAs(UnmanagedType.ByValTStr, SizeConst = CCHDEVICENAME)]
            [System.Runtime.InteropServices.FieldOffset(0)]
            public string dmDeviceName;
            [System.Runtime.InteropServices.FieldOffset(32)]
            public Int16 dmSpecVersion;
            [System.Runtime.InteropServices.FieldOffset(34)]
            public Int16 dmDriverVersion;
            [System.Runtime.InteropServices.FieldOffset(36)]
            public Int16 dmSize;
            [System.Runtime.InteropServices.FieldOffset(38)]
            public Int16 dmDriverExtra;
            [System.Runtime.InteropServices.FieldOffset(40)]
            public DM dmFields;

            [System.Runtime.InteropServices.FieldOffset(44)]
            Int16 dmOrientation;
            [System.Runtime.InteropServices.FieldOffset(46)]
            Int16 dmPaperSize;
            [System.Runtime.InteropServices.FieldOffset(48)]
            Int16 dmPaperLength;
            [System.Runtime.InteropServices.FieldOffset(50)]
            Int16 dmPaperWidth;
            [System.Runtime.InteropServices.FieldOffset(52)]
            Int16 dmScale;
            [System.Runtime.InteropServices.FieldOffset(54)]
            Int16 dmCopies;
            [System.Runtime.InteropServices.FieldOffset(56)]
            Int16 dmDefaultSource;
            [System.Runtime.InteropServices.FieldOffset(58)]
            Int16 dmPrintQuality;

            [System.Runtime.InteropServices.FieldOffset(44)]
            public POINTL dmPosition;
            [System.Runtime.InteropServices.FieldOffset(52)]
            public Int32 dmDisplayOrientation;
            [System.Runtime.InteropServices.FieldOffset(56)]
            public Int32 dmDisplayFixedOutput;

            [System.Runtime.InteropServices.FieldOffset(60)]
            public short dmColor; // See note below!
            [System.Runtime.InteropServices.FieldOffset(62)]
            public short dmDuplex; // See note below!
            [System.Runtime.InteropServices.FieldOffset(64)]
            public short dmYResolution;
            [System.Runtime.InteropServices.FieldOffset(66)]
            public short dmTTOption;
            [System.Runtime.InteropServices.FieldOffset(68)]
            public short dmCollate; // See note below!
            [System.Runtime.InteropServices.FieldOffset(72)]
            [MarshalAs(UnmanagedType.ByValTStr, SizeConst = CCHFORMNAME)]
            public string dmFormName;
            [System.Runtime.InteropServices.FieldOffset(102)]
            public Int16 dmLogPixels;
            [System.Runtime.InteropServices.FieldOffset(104)]
            public Int32 dmBitsPerPel;
            [System.Runtime.InteropServices.FieldOffset(108)]
            public Int32 dmPelsWidth;
            [System.Runtime.InteropServices.FieldOffset(112)]
            public Int32 dmPelsHeight;
            [System.Runtime.InteropServices.FieldOffset(116)]
            public Int32 dmDisplayFlags;
            [System.Runtime.InteropServices.FieldOffset(116)]
            public Int32 dmNup;
            [System.Runtime.InteropServices.FieldOffset(120)]
            public Int32 dmDisplayFrequency;
        }
                
                ..............................
                //Читаем из реестра ключ с DEVMODE принтера
                var dmode = Registry.GetValue(key_preffix + "Printers\\DevModePerUser\\", printer_name, RGDevMode);
                // выделяем память под данные для указателя
                GCHandle pinnedArray = GCHandle.Alloc(dmode, GCHandleType.Pinned);
                //копируем данные по указателю
                IntPtr unmanagedPointer = pinnedArray.AddrOfPinnedObject();
                //копируем данные по указателю в структуру DEVMODE
                var DevMode = (DEVMODE)Marshal.PtrToStructure(unmanagedPointer, typeof(DEVMODE)); 
                //в итоге то что видим в DevMode структуре не выглядит как настройки принтера
                ................................

Declaration DEVMODE spied here
tell me where I made a mistake
Thank you

Answer 1

At the very least, the problem is that the DEVMODE structure can be of different sizes in different versions of .
Programmatically selecting complex printer options in C#

Answer 2

I managed to solve the problem (including the problem of different sizes of DEVMODE. Now I’m finishing the class, if someone is interested, I’ll post it later. The links presented above helped with parsing the structure, but the code presented in them on 7th raises an exception (which, by the way, there are comments under code) it is also not suitable for cases where the size of the DEVMODE structure is floating, so I had to go the other way.

Answer 3

Is it possible to get information about the print job from this structure?