Bitmap类型怎么转换为windwos的HBITMAP(C++)

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Bitmap,HBITMAP

Bitmap类型怎么转换为windwos的HBITMAP(C++)

福昕知识库
2025-12-22

HBITMAP是 Windows GDI（图形设备接口）中的位图句柄（Handle to a Bitmap），在使用C++版本Foxit PDF SDK开发PDF显示预览的图形界面时，经常会用到。

以下是福昕SDK的 C++ 版本的Bitmap类型，转成HBITMAP的示例代码

#include <windows.h>
#include <stdexcept>
#include <cstdint>
#include <algorithm>  

HBITMAP BitmapToHBITMAP( Bitmap& bitmap) {

    if (bitmap.GetWidth() <= 0 || bitmap.GetHeight() <= 0) {
        throw std::invalid_argument("Invalid bitmap width or height");
    }
    int bpp = bitmap.GetBpp();
    int bmp_w = bitmap.GetWidth();
    int bmp_h = bitmap.GetHeight();
    if (bpp != 8 && bpp != 24 && bpp != 32) {
        throw std::invalid_argument("Unsupported BPP: only 8, 24, 32 are allowed");
    }

    const uint8_t* bmpBuffer = bitmap.GetBuffer();
    if (!bmpBuffer) {
        throw std::runtime_error("Bitmap buffer is null");
    }

    BITMAPINFO bmi;
    FillBitmapInfo(bmi, bmp_w, bmp_h, bpp);

    // 获取每个像素的通道数
    int channels = 0;
    if (bpp == 8) {
        channels = 1;
    }
    else if (bpp == 24) {
        channels = 3;
    }
    else if (bpp == 32) {
        channels = 4;
    }
    int rowValidBytes = bmp_w * channels; 

    BYTE* pDibBits = nullptr;
    HBITMAP hBitmap = CreateDIBSection(
        nullptr,           
        &bmi,                 
        DIB_RGB_COLORS,        
        reinterpret_cast<void**>(&pDibBits), 
        nullptr,               
        0                      
    );

    if (!hBitmap || !pDibBits) {
        throw std::runtime_error("Failed to create DIBSection");
    }

    const BYTE* pSrc = reinterpret_cast<const BYTE*>(bmpBuffer);
    for (int row = 0; row < bmp_h; row++) {
        pSrc = reinterpret_cast<const BYTE*>(bmpBuffer) + row * bitmap.GetPitch();
        BYTE* pDst = &pDibBits[row * rowValidBytes];

        // 复制有效像素数据
        memcpy(pDst, pSrc, rowValidBytes);
        if (bpp == 24) {
            for (int col = 0; col < bmp_w; col++) {
                std::swap(pDst[col * 3 + 0], pDst[col * 3 + 2]);
            }
        }
        else if (bpp == 32) {
            for (int col = 0; col < bmp_w; col++) {
                std::swap(pDst[col * 4 + 0], pDst[col * 4 + 2]);
            }
        }
    }
return hBitmap;
}