Windows USB打印机打印进度信息

我需要写一个程序，找到所有连接的USB打印机的Windows PC和发送一个文件到选定的打印机从这个列表。这两点都没有问题，而且效果很好

第一点

但现在我的问题来了

我必须打印超过100000页的非常大的文件，操作员希望查看当前打印的页面数。有可能得到这个信息吗？例如，每3秒，以便我可以在屏幕上显示

下面是关于RawPrinterHelper类的更多信息。它不包含回调。我必须如何定义回调函数

---

您可能需要添加与语言相应的标记。如果RawPrinterHelper不支持回调以提供状态信息，您很可能运气不佳。上述问题必须用C语言解决。

        var printerQuery = new ManagementObjectSearcher("SELECT * from Win32_Printer");
        i = 1;
        foreach (var printer in printerQuery.Get())
        {
            var name = printer.GetPropertyValue("Name");
            var status = printer.GetPropertyValue("Status");
            var isDefault = printer.GetPropertyValue("Default");
            var isNetworkPrinter = printer.GetPropertyValue("Network");
            var PortName = printer.GetPropertyValue("PortName");
            bool Connected = (bool)printer.GetPropertyValue("WorkOffline");
            var Caption = printer.GetPropertyValue("Caption");

            string s = "Name: " + name;
            string nbr = "";
            if (i.ToString().Length < 2) nbr = "0";
            nbr += i.ToString();
            listBoxUSBInfo.Items.Add(nbr + ": " + s);
            listBoxUSBInfo.Items.Add("      Status: " + status);
            listBoxUSBInfo.Items.Add("      Default: " + isDefault);
            listBoxUSBInfo.Items.Add("      Network: " + isNetworkPrinter);
            listBoxUSBInfo.Items.Add("      PortName: " + PortName);
            if ( Connected) listBoxUSBInfo.Items.Add("      Connected: True");
            if (!Connected) listBoxUSBInfo.Items.Add("      Connected: False");
            listBoxUSBInfo.Items.Add("      Caption: " + Caption);

            i++;
        }

RawPrinterHelper.SendFileToPrinter("PrinterName", "FileName");

public class RawPrinterHelper
{
    // Structure and API declarions:
    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Ansi)]
    public class DOCINFOA
    {
        [MarshalAs(UnmanagedType.LPStr)]
        public string pDocName;
        [MarshalAs(UnmanagedType.LPStr)]
        public string pOutputFile;
        [MarshalAs(UnmanagedType.LPStr)]
        public string pDataType;
    }
    [DllImport("winspool.Drv", EntryPoint = "OpenPrinterA", SetLastError = true, CharSet = CharSet.Ansi, ExactSpelling = true, CallingConvention = CallingConvention.StdCall)]
    public static extern bool OpenPrinter([MarshalAs(UnmanagedType.LPStr)] string szPrinter, out IntPtr hPrinter, IntPtr pd);

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

    [DllImport("winspool.Drv", EntryPoint = "StartDocPrinterA", SetLastError = true, CharSet = CharSet.Ansi, ExactSpelling = true, CallingConvention = CallingConvention.StdCall)]
    public static extern bool StartDocPrinter(IntPtr hPrinter, Int32 level, [In, MarshalAs(UnmanagedType.LPStruct)] DOCINFOA di);

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

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

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

    [DllImport("winspool.Drv", EntryPoint = "WritePrinter", SetLastError = true, ExactSpelling = true, CallingConvention = CallingConvention.StdCall)]
    public static extern bool WritePrinter(IntPtr hPrinter, IntPtr pBytes, Int32 dwCount, out Int32 dwWritten);

    // SendBytesToPrinter()
    // When the function is given a printer name and an unmanaged array
    // of bytes, the function sends those bytes to the print queue.
    // Returns true on success, false on failure.
    public static bool SendBytesToPrinter(string szPrinterName, IntPtr pBytes, Int32 dwCount)
    {
        Int32 dwError = 0, dwWritten = 0;
        IntPtr hPrinter = new IntPtr(0);
        DOCINFOA di = new DOCINFOA();
        bool bSuccess = false; // Assume failure unless you specifically succeed.

        di.pDocName = "My C#.NET RAW Document";
        di.pDataType = "RAW";

        // Open the printer.
        if (OpenPrinter(szPrinterName.Normalize(), out hPrinter, IntPtr.Zero))
        {
            // Start a document.
            if (StartDocPrinter(hPrinter, 1, di))
            {
                // Start a page.
                if (StartPagePrinter(hPrinter))
                {
                    // Write your bytes.
                    bSuccess = WritePrinter(hPrinter, pBytes, dwCount, out dwWritten);
                    EndPagePrinter(hPrinter);
                }
                EndDocPrinter(hPrinter);
            }
            ClosePrinter(hPrinter);
        }
        // If you did not succeed, GetLastError may give more information
        // about why not.
        if (bSuccess == false)
        {
            dwError = Marshal.GetLastWin32Error();
        }
        return bSuccess;
    }

    public static bool SendFileToPrinter(string szPrinterName, string szFileName)
    {
        // Open the file.
        FileStream fs = new FileStream(szFileName, FileMode.Open);
        // Create a BinaryReader on the file.
        BinaryReader br = new BinaryReader(fs);
        // Dim an array of bytes big enough to hold the file's contents.
        Byte[] bytes = new Byte[fs.Length];
        bool bSuccess = false;
        // Your unmanaged pointer.
        IntPtr pUnmanagedBytes = new IntPtr(0);
        int nLength;

        nLength = Convert.ToInt32(fs.Length);
        // Read the contents of the file into the array.
        bytes = br.ReadBytes(nLength);
        // Allocate some unmanaged memory for those bytes.
        pUnmanagedBytes = Marshal.AllocCoTaskMem(nLength);
        // Copy the managed byte array into the unmanaged array.
        Marshal.Copy(bytes, 0, pUnmanagedBytes, nLength);
        // Send the unmanaged bytes to the printer.
        bSuccess = SendBytesToPrinter(szPrinterName, pUnmanagedBytes, nLength);
        // Free the unmanaged memory that you allocated earlier.
        Marshal.FreeCoTaskMem(pUnmanagedBytes);
        fs.Close();
        return bSuccess;
    }

    public static bool SendStringToPrinter(string szPrinterName, string szString)
    {
        IntPtr pBytes;
        Int32 dwCount;
        // How many characters are in the string?
        dwCount = szString.Length;
        // Assume that the printer is expecting ANSI text, and then convert
        // the string to ANSI text.
        pBytes = Marshal.StringToCoTaskMemAnsi(szString);
        // Send the converted ANSI string to the printer.
        SendBytesToPrinter(szPrinterName, pBytes, dwCount);
        Marshal.FreeCoTaskMem(pBytes);
        return true;
    }
} // public class RawPrinterHelper