C# C++打印机打印文档监控 监控打印机打印进度并保存打印文档

可以使用Windows的API函数来监控打印机打印的文档。具体的实现可以通过以下步骤来完成：

1. 调用Windows API函数”SetWindowsHookEx”来安装一个打印监控钩子函数。
2. 在钩子函数中，可以通过监控打印机发送的消息来获取正在打印的文档的相关信息，如文档的名称、打印机的名称、打印进度等。
3. 当监测到有文档正在打印时，可以执行相关操作，如将文档保存到指定的位置、发送邮件等。

下面是一个简单的C++示例代码，用于在Windows中监控打印机打印的文档并输出相关信息：

#include <Windows.h>
#include <Winspool.h>

// 打印机钩子函数
LRESULT CALLBACK PrintMonitorProc(int nCode, WPARAM wParam, LPARAM lParam) {
    if (nCode == HC_ACTION && wParam == JOB_STATUS) {
        JOB_INFO_2* pJobInfo = (JOB_INFO_2*)lParam;
        // 打印机名称
        LPCWSTR pszPrinterName = pJobInfo->pPrinterName;
        // 文档名称
        LPCWSTR pszDocumentName = pJobInfo->pDocument;
        // 打印进度
        DWORD dwJobStatus = pJobInfo->Status;
        // 输出文档信息
        wprintf(L"Printer Name: %s\nDocument Name: %s\nJob Status: %d\n\n", 
            pszPrinterName, pszDocumentName, dwJobStatus);
    }
    return CallNextHookEx(NULL, nCode, wParam, lParam);
}

int main() {
    HMODULE hWinSpool = LoadLibrary(TEXT("winspool.drv"));
    if (hWinSpool == NULL) {
        return 1;
    }

    // 安装打印机钩子
    HHOOK hPrintHook = SetWindowsHookEx(WH_JOBNOTIFY, PrintMonitorProc, hWinSpool, 0);
    if (hPrintHook == NULL) {
        return 1;
    }

    // 消息循环
    MSG msg;
    while (GetMessage(&msg, NULL, 0, 0) > 0) {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }

    // 卸载钩子
    UnhookWindowsHookEx(hPrintHook);
    FreeLibrary(hWinSpool);

    return 0;
}

需要注意的是，打印机钩子函数需要以DLL的形式编写，并在安装钩子时指定DLL的路径。在钩子函数中，可以调用相关的DLL函数来实现保存文档等操作。

C#代码示例

using System;
using System.Runtime.InteropServices;
using System.Drawing.Printing;

class PrintMonitor {
    // 声明打印机钩子委托
    public delegate int PrintHookProc(int nCode, int wParam, IntPtr lParam);

    // 声明Win32 API函数
    [DllImport("winspool.drv")]
    public static extern bool SetJobA(IntPtr hPrinter, int JobId, int Level, IntPtr pJob, int Command);

    [DllImport("user32.dll")]
    public static extern IntPtr SetWindowsHookEx(int idHook, PrintHookProc lpfn, IntPtr hMod, uint dwThreadId);

    [DllImport("user32.dll")]
    public static extern int CallNextHookEx(IntPtr hhk, int nCode, int wParam, IntPtr lParam);

    [DllImport("user32.dll")]
    public static extern bool UnhookWindowsHookEx(IntPtr hhk);

    [DllImport("kernel32.dll")]
    public static extern int GetCurrentThreadId();

    // 打印机钩子函数
    public static int PrintMonitorProc(int nCode, int wParam, IntPtr lParam) {
        if (nCode == 0 && wParam == 0x202) {  // JOB_STATUS message
            var jobInfo = (JOB_INFO_2)Marshal.PtrToStructure(lParam, typeof(JOB_INFO_2));
            // 打印机名称
            string printerName = jobInfo.pPrinterName;
            // 文档名称
            string documentName = jobInfo.pDocument;
            // 打印进度
            int jobStatus = (int)jobInfo.Status;
            // 输出文档信息
            Console.WriteLine($"Printer Name: {printerName}");
            Console.WriteLine($"Document Name: {documentName}");
            Console.WriteLine($"Job Status: {jobStatus}");
            Console.WriteLine();
        }
        return CallNextHookEx(IntPtr.Zero, nCode, wParam, lParam);
    }

    // 安装打印机钩子
    public static IntPtr SetPrintHook() {
        IntPtr hMod = Marshal.GetHINSTANCE(typeof(PrintMonitor).Assembly.GetModules()[0]);
        var printHook = new PrintHookProc(PrintMonitorProc);
        return SetWindowsHookEx(27, printHook, hMod, (uint)GetCurrentThreadId());
    }

    // 卸载打印机钩子
    public static void UnsetPrintHook(IntPtr hookHandle) {
        UnhookWindowsHookEx(hookHandle);
    }

    // 定义JOB_INFO_2结构体
    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Auto)]
    public struct JOB_INFO_2 {
        public int JobId;
        public string pPrinterName;
        public string pMachineName;
        public string pUserName;
        public string pDocument;
        public string pDatatype;
        public string pStatus;
        public int Status;
        public int Priority;
        public int Position;
        public int TotalPages;
        public int PagesPrinted;
        public SystemTime Submitted;
        public int Size;
        public string pComment;
        public string pDevMode;
        public string pSecurityDescriptor;
        public int Attributes;
        public int Reserved;


    // 定义SYSTEMTIME结构体
    [StructLayout(LayoutKind.Sequential)]
    public struct SystemTime {
        public short wYear;
        public short wMonth;
        public short wDayOfWeek;
        public short wDay;
        public short wHour;
    }