c++在windows平台下使用ghostscript的api接口静默打印pdf

Ghostscript是一款开源的PostScript和PDF解释器，可以在Windows平台下使用其API接口进行静默打印PDF。

以下是实现步骤：

1. 下载并安装Ghostscript

从Ghostscript官网（https://www.ghostscript.com/download/gsdnld.html）下载Windows平台下的安装程序，安装到本地计算机上。

2. 编写代码

使用Ghostscript提供的API接口，在代码中实现PDF文件的静默打印。以下是一个示例代码：

#include <stdio.h>
#include "gsapi.h"

int main(int argc, char *argv[])
{
    const char *pdfFile = "C:\\test.pdf";
    const char *printerName = "My Printer";
    const char *deviceName = "mswinpr2";
    const char *outputFile = "C:\\test.prn";
    const char *outputFormat = "PRN";
    const char *args[] = {
        "pdf2ps", "-sDEVICE=mswinpr2",
        "-sOutputFile=C:\\test.prn",
        "-dNOPAUSE", "-dBATCH", "-dSAFER",
        "C:\\test.pdf", NULL
    };
    int argcCount = sizeof(args) / sizeof(args[0]) - 1;

    gsapi_restart_ijs(NULL);
    gsapi_revision_t revision;
    gsapi_revision(&revision, sizeof(revision));
    printf("Ghostscript version: %d.%d.%d\n", revision.product, revision.major, revision.minor);

    gsapi_instance *instance;
    int errorCode = gsapi_new_instance(&instance, NULL);
    if (errorCode < 0) {
        printf("Failed to create Ghostscript instance: %d\n", errorCode);
        return -1;
    }

    gsapi_set_stdio(instance, stdin, stdout, stderr);
    gsapi_set_poll(instance, NULL);

    errorCode = gsapi_init_with_args(instance, argcCount, (char **)args);
    if (errorCode < 0) {
        printf("Failed to initialize Ghostscript instance: %d\n", errorCode);
        return -1;
    }

    errorCode = gsapi_exit(instance);
    if (errorCode < 0) {
        printf("Failed to exit Ghostscript instance: %d\n", errorCode);
        return -1;
    }

    // Send the output file to the printer
    HANDLE printerHandle;
    DOC_INFO_1 docInfo;
    DWORD bytesWritten;
    BOOL success;

    success = OpenPrinter((LPSTR) printerName, &printerHandle, NULL);
    if (!success) {
        printf("Failed to open printer: %d\n", GetLastError());
        return -1;
    }

    docInfo.pDocName = "Test Document";
    docInfo.pOutputFile = NULL;
    docInfo.pDatatype = "RAW";
    success = StartDocPrinter(printerHandle, 1, (LPBYTE) &docInfo);
    if (!success) {
        printf("Failed to start print job: %d\n", GetLastError());
        ClosePrinter(printerHandle);
        return -1;
    }

    success = StartPagePrinter(printerHandle);
    if (!success) {
        printf("Failed to start page: %d\n", GetLastError());
        EndDocPrinter(printerHandle);
        ClosePrinter(printerHandle);
        return -1;
    }

    HANDLE fileHandle = CreateFile(outputFile, GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
    if (fileHandle == INVALID_HANDLE_VALUE) {
        printf("Failed to open output file: %d\n", GetLastError());
        EndPagePrinter(printerHandle);
        EndDocPrinter(printerHandle);
        ClosePrinter(printerHandle);
        return -1;
    }

    BYTE buffer[4096];
    DWORD bytesRead;

    while (ReadFile(fileHandle, buffer, sizeof(buffer), &bytesRead, NULL)) {
        if (bytesRead == 0) {
            break;
        }

        success = WritePrinter(printerHandle, buffer, bytesRead, &bytesWritten);
        if (!success) {
            printf("Failed to write to printer: %d\n", GetLastError());
            CloseHandle(fileHandle);
            EndPagePrinter(printerHandle);
            EndDocPrinter(printerHandle);
            ClosePrinter(printerHandle);
            return -1;
        }
    }

    CloseHandle(fileHandle);

    success = EndPagePrinter(printerHandle);
    if (!success) {
        printf("Failed to end page: %d\n", GetLastError());
        EndDocPrinter(printerHandle);
        ClosePrinter(printerHandle);
        return -1;
    }

    success = EndDocPrinter(printerHandle);
    if (!success) {
        printf("Failed to end print job: %d\n", GetLastError());
        ClosePrinter(printerHandle);
        return -1;
    }

    ClosePrinter(printerHandle);

    return 0;
}

3. 编译和运行

使用Visual Studio等编译器编译代码，生成可执行文件。在命令行中运行可执行文件，即可实现PDF文件的静默打印。

> ghostprint.exe

该示例代码将PDF文件转换为PRN格式的文件，并发送到指定的打印机进行打印。可以根据实际需求修改代码中的参数和变量。