PDF 开源库libharu

来源：互联网发布：js 地图插件编辑：程序博客网时间：2024/05/16 07:33

libharu是一套开源的写pdf库，可以创建，添加页，写字，画图，载入图像等。

它的下载页面是： http://libharu.org/wiki/Downloads

下面我说一下在Windows下编译并测试的步骤。

一、编译

1、首先要准备俩个库，libpng和zlib。libpng在目录../projects/visualc6/下有vc6的工程可以直接编译。

zlib可以用nmake编译它的makefile。

2、在libharu目录下nmake，生成libhpdf.lib，这样就可以调用里面的api了，也可以生成dll，编译其中的dll版本的Makefile就可以。

二、测试程序

1、新建基于Console的程序。

2、加入静态库

#pragma comment(lib, "lib/libhpdf.lib")
#pragma comment(lib, "lib/zlib.lib")
#pragma comment(lib, "lib/libpng.lib")

3、这个demo实现加入图片，准备俩个png图片，在同一页绘制出来，然后导出到pdf文件。

完整的代码如下：

#include "windows.h"
#include "include/hpdf.h"
#include <setjmp.h>
#include <stdio.h>

#pragma comment(lib, "lib/libhpdf.lib")
#pragma comment(lib, "lib/zlib.lib")
#pragma comment(lib, "lib/libpng.lib")

jmp_buf env;

void
error_handler (HPDF_STATUS   error_no,
                HPDF_STATUS   detail_no,
                void         *user_data)
{
    printf ("ERROR: error_no=%04X, detail_no=%u/n", (HPDF_UINT)error_no,
        (HPDF_UINT)detail_no);
    longjmp(env, 1);
}

int main(int nArgc, char** pArgv)
{
    HPDF_Doc pdf;
    HPDF_Page page;
    HPDF_Destination dst;
    HPDF_Font font;
    HPDF_Image hpdfImage;

    pdf = HPDF_New (error_handler, NULL);
    if (!pdf) {
        printf ("ERROR: cannot create pdf object./n");
        return 1;
    }

    if (setjmp(env)) {
        HPDF_Free (pdf);
        return 1;
    }

//    HPDF_SetCompressionMode (pdf, HPDF_COMP_ALL);

    font = HPDF_GetFont (pdf, "Helvetica", NULL);

    char * pstrPath[2] = {
        "e://a.png",
        "e://read_book.png"
    };

    hpdfImage = HPDF_LoadPngImageFromFile(pdf, pstrPath[0]);

    /* add a new page object. */
    page = HPDF_AddPage (pdf);

    dst = HPDF_Page_CreateDestination (page);
    HPDF_Destination_SetXYZ (dst, 0, HPDF_Page_GetHeight (page), 1);
    HPDF_SetOpenAction(pdf, dst);

    HPDF_Page_SetHeight (page, HPDF_Image_GetHeight(hpdfImage));
    HPDF_Page_SetWidth (page, HPDF_Image_GetWidth(hpdfImage));

    HPDF_Page_SetFontAndSize (page, font, 12);

    unsigned int oldWidth = HPDF_Image_GetWidth(hpdfImage);

    for (int i = 0; i < 2; i ++)
    {
        /*

        HPDF_Page_SetRGBFill (page, 1.0, 0, 0);
        HPDF_Page_MoveTo (page, 100, 100);
        HPDF_Page_LineTo (page, 100, 180);
        */

    //    HPDF_SetPageMode(pdf, HPDF_PAGE_MODE_FULL_SCREEN);
        hpdfImage = HPDF_LoadPngImageFromFile(pdf, pstrPath[i]);

        if (hpdfImage)
        {
            int x = 0;
            int y = 0;
            if (i == 1)
            {
                x = oldWidth - HPDF_Image_GetWidth(hpdfImage) - 3;
            }

            HPDF_Page_DrawImage(page,
                                hpdfImage,
                                x, y,
                                HPDF_Image_GetWidth(hpdfImage),
                                HPDF_Image_GetHeight(hpdfImage));
        }
    }

    /* save the document to a file */
    HPDF_SaveToFile (pdf, "e://test.pdf");
    /* clean up */
    HPDF_Free (pdf);

    return 0;
}