打印机属性对话框不会使用文档属性保存修改后的属性

Question

在引用了代码项目，msdn论坛，堆栈溢出等不同的论坛和文章之后，建议使用以下代码段打开打印机属性对话框并保存修改后的更改，但仅打开属性对话框，但更改对打印机属性所做的设置不会保存。我正在从WPF应用程序中调用以下方法。有人可以看看吗，让我知道是否遗漏了任何东西？

        /// Open the printer preferences prompt. 
    /// </summary>
    /// <param name="printerSettings">settings of the printer to be used</param>
    /// <returns>
    public void OpenPrinterPropertiesDialog(PrinterSettings printerSettings)
    {
        IntPtr hDevMode = IntPtr.Zero;
        IntPtr pDevMode = IntPtr.Zero;
        IntPtr devModeData = IntPtr.Zero;
        try
        {
            PRINTER_DEFAULTS pd = default(PRINTER_DEFAULTS);
            IntPtr hPrinter = default(IntPtr);
            int nRet = 0;
            pd.DesiredAccess = PRINTER_ACCESS_USE;
            // Open the printer by name
            nRet = OpenPrinter(printerSettings.PrinterName, out hPrinter, ref pd);
            // Get devmode handle from printer settings
            hDevMode = printerSettings.GetHdevmode(printerSettings.DefaultPageSettings);
            // Lock the devmode
            pDevMode = GlobalLock(hDevMode);
            //Fetch the size needed to allocate memory
            int sizeNeeded = DocumentProperties(IntPtr.Zero, hPrinter, printerSettings.PrinterName, IntPtr.Zero, pDevMode, 0);
            devModeData = Marshal.AllocHGlobal(sizeNeeded);
            // Show the native printer preferences dialog
            DocumentProperties(IntPtr.Zero, hPrinter, printerSettings.PrinterName, devModeData, pDevMode, DM_IN_BUFFER | DM_PROMPT | DM_OUT_BUFFER);
            // UnLock the devmode
            GlobalUnlock(hDevMode);
            // Close Printer
            ClosePrinter(hPrinter);
            // Get settings and page settings from changed DEVMODE
            printerSettings.SetHdevmode(devModeData);
            printerSettings.DefaultPageSettings.SetHdevmode(devModeData);
            // Free memory
            GlobalFree(hDevMode);
        }

        finally
        {
            if (hDevMode != IntPtr.Zero)
            {
                Marshal.FreeHGlobal(hDevMode);
            }
            if (pDevMode != IntPtr.Zero)
            {
                Marshal.FreeHGlobal(devModeData);
            }
            if (devModeData != IntPtr.Zero)
            {
                Marshal.FreeHGlobal(devModeData);
            }
        }
    }

 // Win32 API Declaration

    [DllImport("kernel32.dll")]
    static extern IntPtr GlobalLock(IntPtr hMem);

    [DllImport("kernel32.dll")]
    static extern bool GlobalUnlock(IntPtr hMem);

    [DllImport("kernel32.dll")]
    static extern bool GlobalFree(IntPtr hMem);

    [DllImport("winspool.Drv", EntryPoint = "ClosePrinter", SetLastError = true, ExactSpelling = true, CallingConvention = CallingConvention.StdCall)]
    public static extern bool ClosePrinter(IntPtr hPrinter);

    [DllImport("winspool.Drv", EntryPoint = "DocumentPropertiesA", SetLastError = true, ExactSpelling = true, CallingConvention = CallingConvention.StdCall)]
    static extern int DocumentProperties(IntPtr hwnd, IntPtr hPrinter,
       [MarshalAs(UnmanagedType.LPStr)] string pDeviceName,
       IntPtr pDevModeOutput, IntPtr pDevModeInput, int fMode);

    [DllImport("winspool.drv", CharSet = CharSet.Auto, SetLastError = true)]
    static extern int OpenPrinter(string pPrinterName, out IntPtr phPrinter, ref PRINTER_DEFAULTS pDefault);