MFC 屏幕截图方法

//获取当前屏幕的并且保存图片
LRESULT CFeetScanView::SaveViewBMP(WPARAM wParam, LPARAM lParam)
{
    CRect rect;
    this->GetClientRect(&rect);
    rect.left = ;
    rect.top = ;
    CBitmap m_bitmap;
    m_bitmap.m_hObject = CopyScreenToBitmap(rect);

    char szFileName[_MAX_PATH];
    char szPath[_MAX_PATH];
    GetConfigMgr()->GetModuleDirectory( szPath);
    sprintf( szFileName, "%s\\image.png", szPath);
    SaveBitmapToFile(m_bitmap,szFileName);
    return ;
}

HBITMAP CFeetScanView::CopyScreenToBitmap(LPRECT lpRect)
{
   // 屏幕和内存设备描述表
    HDC hScrDC=, hMemDC;
    // 位图句柄
    HBITMAP hBitmap, hOldBitmap;
    // 选定区域坐标
    int nX, nY, nX2, nY2;
    // 位图宽度和高度
    int nWidth, nHeight;
    // 屏幕分辨率
    int xScrn, yScrn;
    // 确保选定区域不为空矩形
    // if (IsRectEmpty(lpRect))
    // return NULL;
    //为屏幕创建设备描述表
    hScrDC = CreateDC( "DISPLAY", NULL, NULL, NULL);
    //
    int ok=;
    if(hScrDC==NULL)  //如果创建失败
    {
        ok=;
    }
    //为屏幕设备描述表创建兼容的内存设备描述表
    hMemDC = CreateCompatibleDC(hScrDC);
    // 获得选定区域坐标
    nX = lpRect-> left;
    nY = lpRect-> top;
    nX2 = lpRect-> right;
    nY2 = lpRect-> bottom;
    // 获得屏幕分辨率
    xScrn = GetDeviceCaps(hScrDC, HORZRES);
    yScrn = GetDeviceCaps(hScrDC, VERTRES);
    //确保选定区域是可见的
    if (nX <)
        nX = ;
    if (nY < )
        nY = ;
    if (nX2 > xScrn)
        nX2 = xScrn;
    if (nY2 > yScrn)
        nY2 = yScrn;
    nWidth = nX2 - nX;
    nHeight = nY2 - nY; 

    // 创建一个与屏幕设备描述表兼容的位图
    hBitmap = CreateCompatibleBitmap(hScrDC, nWidth, nHeight); 

    // 把新位图选到内存设备描述表中
    hOldBitmap = (HBITMAP)SelectObject(hMemDC, hBitmap); 

    // 把屏幕设备描述表拷贝到内存设备描述表中
    BitBlt(hMemDC, , , nWidth, nHeight,hScrDC, nX, nY, SRCCOPY); 

    //得到屏幕位图的句柄
    hBitmap =(HBITMAP)SelectObject(hMemDC, hOldBitmap); 

    //清除
    DeleteDC(hScrDC);
    DeleteDC(hMemDC); 

    // 返回位图句柄
    return hBitmap;
}

BOOL CFeetScanView::SaveBitmapToFile(HBITMAP hBitmap, LPCTSTR lpFileName )
{
    HDC hDC; //设备描述表
    int iBits; //当前显示分辨率下每个像素所占字节数
    WORD wBitCount; //位图中每个像素所占字节数
    DWORD dwPaletteSize=, //定义调色板大小， 位图中像素字节大小 ，位图文件大小 ， 写入文件字节数
        dwBmBitsSize,
        dwDIBSize, dwWritten;
    BITMAP Bitmap; //位图属性结构
    BITMAPFILEHEADER bmfHdr; //位图文件头结构
    BITMAPINFOHEADER bi; //位图信息头结构
    LPBITMAPINFOHEADER lpbi; //指向位图信息头结构 

    HANDLE fh, hDib, hPal,hOldPal=NULL; //定义文件，分配内存句柄，调色板句柄 

    //计算位图文件每个像素所占字节数
    HDC hWndDC = CreateDC("DISPLAY",NULL,NULL,NULL);
    hDC = ::CreateCompatibleDC( hWndDC ) ;
    iBits = GetDeviceCaps(hDC, BITSPIXEL) * GetDeviceCaps(hDC, PLANES);
    DeleteDC(hDC); 

    if (iBits <= )
        wBitCount = ;
    else if (iBits <= )
        wBitCount = ;
    else if (iBits <= )
        wBitCount = ;
    else if (iBits <= )
        wBitCount = ;
    else
        wBitCount =  ; 

    //计算调色板大小
    if (wBitCount <= )
        dwPaletteSize = ( << wBitCount) * sizeof(RGBQUAD); 

    //设置位图信息头结构
    GetObject(hBitmap, sizeof(BITMAP), (LPSTR)&Bitmap);
    bi.biSize = sizeof(BITMAPINFOHEADER);
    bi.biWidth = Bitmap.bmWidth;
    bi.biHeight = Bitmap.bmHeight;
    bi.biPlanes = ;
    bi.biBitCount = wBitCount;
    bi.biCompression = BI_RGB;
    bi.biSizeImage = ;
    bi.biXPelsPerMeter = ;
    bi.biYPelsPerMeter = ;
    bi.biClrUsed = ;
    bi.biClrImportant = ; 

    dwBmBitsSize = ((Bitmap.bmWidth * wBitCount+)/) *  * Bitmap.bmHeight ; 

    //为位图内容分配内存
    hDib = GlobalAlloc(GHND,dwBmBitsSize+dwPaletteSize+sizeof(BITMAPINFOHEADER));
    lpbi = (LPBITMAPINFOHEADER)GlobalLock(hDib);
    *lpbi = bi; 

    // 处理调色板
    hPal = GetStockObject(DEFAULT_PALETTE);
    if (hPal)
    {
        hDC = ::GetDC(NULL);
        hOldPal = ::SelectPalette(hDC, (HPALETTE)hPal, FALSE);
        RealizePalette(hDC);
    } 

    // 获取该调色板下新的像素值
    GetDIBits(hDC, hBitmap, , (UINT) Bitmap.bmHeight,
        (LPSTR)lpbi + sizeof(BITMAPINFOHEADER)
        +dwPaletteSize,
        (LPBITMAPINFO )
        lpbi, DIB_RGB_COLORS); 

    //恢复调色板
    if (hOldPal)
    {
        SelectPalette(hDC, (HPALETTE)hOldPal, TRUE);
        RealizePalette(hDC);
        ::ReleaseDC(NULL, hDC);
    } 

    //创建位图文件
    fh = CreateFile(lpFileName, GENERIC_WRITE,
        , NULL, CREATE_ALWAYS,
        FILE_ATTRIBUTE_NORMAL | FILE_FLAG_SEQUENTIAL_SCAN, NULL); 

    if (fh == INVALID_HANDLE_VALUE)
        return FALSE; 

    // 设置位图文件头
    bmfHdr.bfType = 0x4D42; // "BM"
    dwDIBSize = sizeof(BITMAPFILEHEADER)
        + sizeof(BITMAPINFOHEADER)
        + dwPaletteSize + dwBmBitsSize;
    bmfHdr.bfSize = dwDIBSize;
    bmfHdr.bfReserved1 = ;
    bmfHdr.bfReserved2 = ;
    bmfHdr.bfOffBits = (DWORD)sizeof(BITMAPFILEHEADER)
        + (DWORD)sizeof(BITMAPINFOHEADER)
        + dwPaletteSize; 

    // 写入位图文件头
    WriteFile(fh, (LPSTR)&bmfHdr, sizeof(BITMAPFILEHEADER), &dwWritten, NULL); 

    // 写入位图文件其余内容
    WriteFile(fh, (LPSTR)lpbi, dwDIBSize,
        &dwWritten, NULL); 

    //清除
    GlobalUnlock(hDib);
    GlobalFree(hDib);
    CloseHandle(fh); 

    return TRUE; 

}

//将当前的图片进行90度显示出来
    CDC* pDC1 = m_left_pic.GetDC();
    Graphics graph(pDC1->GetSafeHdc());
    CRect rect;
    m_left_pic.GetClientRect(rect);

    char szFileName[_MAX_PATH];
    char szPath[_MAX_PATH];
    GetConfigMgr()->GetModuleDirectory( szPath);
    sprintf( szFileName, "%s\\image.png", szPath);
    WCHAR wszWideString[_MAX_PATH];
    wcscpy(wszWideString, CT2CW(szFileName));
    Image image(wszWideString);

    REAL width  = (REAL)image.GetWidth();
    REAL height = (REAL)image.GetHeight();
    int nX = ;
    int nY = ;
    Point point90[] = {
        Point(nX + height,nY),
        Point(nX + height,nY+width),
        Point(nX,nY)
    };

    graph.DrawImage(&image, point90,);
    ReleaseDC(pDC1);