截屏代码

#define ALIGNEDONDWORD(theBytes) ( ( ( (DWORD)(theBytes) + 31 ) & ~31 ) >> 3 )

BOOL BmpFromHandle( HDC hDC, HBITMAP hBitmap, WORD nBits, LPCTSTR lpszFile )
{
    BITMAP bmp;
    WORD cClrBits;
    LPBITMAPINFO bi;
    BITMAPFILEHEADER bf;
    LPVOID lpData;
    HANDLE hFile;
    DWORD dwBytes;
    int nRet;
    BOOL bRet;

    nRet = ::GetObject( ( HANDLE )hBitmap, sizeof( BITMAP ), &bmp );
    if ( nRet != sizeof( BITMAP ) )
    {
        return FALSE;
    }

    bmp.bmBitsPixel = nBits;

    cClrBits = ( WORD )( bmp.bmPlanes * bmp.bmBitsPixel );

    if ( cClrBits == 1 )
    {
        cClrBits = 1;
    }
    else if ( cClrBits <= 4 )
    {
        cClrBits = 4;
    }
    else if ( cClrBits <= 8 )
    {
        cClrBits = 8;
    }
    else if ( cClrBits <= 16 )
    {
        cClrBits = 16;
    }
    else if ( cClrBits <= 24 )
    {
        cClrBits = 24;
    }
    else
    {
        cClrBits = 32;
    }

    if ( cClrBits < 24 )
    {
        bi = ( LPBITMAPINFO )calloc( 1, sizeof( BITMAPINFOHEADER ) + sizeof( RGBQUAD ) * ( 1 << cClrBits ) );
    }
    else
    {
        bi = ( LPBITMAPINFO )calloc( 1, sizeof( BITMAPINFOHEADER ) );
    }

    if ( bi == NULL )
    {
        return FALSE;
    }

    bi->bmiHeader.biSize = sizeof( BITMAPINFOHEADER );
    bi->bmiHeader.biWidth = bmp.bmWidth;
    bi->bmiHeader.biHeight = bmp.bmHeight;
    bi->bmiHeader.biPlanes = bmp.bmPlanes;
    bi->bmiHeader.biBitCount = bmp.bmBitsPixel;
    bi->bmiHeader.biCompression = BI_RGB;
    bi->bmiHeader.biSizeImage = ( ( ( bi->bmiHeader.biWidth * cClrBits + 31 ) & ~31 ) >> 3 ) * bi->bmiHeader.biHeight;
    /*bi->bmiHeader.biXPelsPerMeter = 0;
    bi->bmiHeader.biYPelsPerMeter = 0;*/

    if ( cClrBits < 24 )
    {
        bi->bmiHeader.biClrUsed = ( 1 << cClrBits );
    }
    /*else
    {
        bi->bmiHeader.biClrUsed = 0;
    }*/

    /*bi->bmiHeader.biClrImportant = 0;*/


    lpData = calloc( ( bi->bmiHeader.biSizeImage + 4095 ) >> 12, 4096 );
    if ( lpData == NULL )
    {
        free( bi );
        return FALSE;
    }

    nRet = ::GetDIBits( hDC, hBitmap, 0, bi->bmiHeader.biHeight, lpData, bi, DIB_RGB_COLORS );
    if ( nRet != bi->bmiHeader.biHeight )
    {
        goto err_exit;
    }

    if ( cClrBits < 24 )
    {
        bi->bmiHeader.biClrUsed = ( 1 << cClrBits );
    }

    memset( &bf, 0, sizeof( BITMAPFILEHEADER ) );
    bf.bfType = 0x4d42;
    bf.bfSize = sizeof( BITMAPFILEHEADER ) + sizeof( BITMAPINFOHEADER ) + bi->bmiHeader.biClrUsed * sizeof( RGBQUAD ) + bi->bmiHeader.biSizeImage;
    /*bf.bfReserved1 = 0;
    bf.bfReserved2 = 0;*/
    bf.bfOffBits = bf.bfSize - bi->bmiHeader.biSizeImage;

    hFile = ::CreateFile( lpszFile, GENERIC_WRITE, 0, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL );
    if ( hFile == INVALID_HANDLE_VALUE )
    {
        goto err_exit;
    }

    bRet = ::WriteFile( hFile, &bf, sizeof( BITMAPFILEHEADER ), &dwBytes, NULL );
    if ( !bRet || dwBytes != sizeof( BITMAPFILEHEADER ) )
    {
        ::CloseHandle( hFile );
        goto err_exit;
    }

    bRet = ::WriteFile( hFile, bi, bf.bfOffBits - sizeof( BITMAPFILEHEADER ), &dwBytes, NULL );
    if ( !bRet || dwBytes != bf.bfOffBits - sizeof( BITMAPFILEHEADER ) )
    {
        ::CloseHandle( hFile );
        goto err_exit;
    }

    bRet = ::WriteFile( hFile, lpData, bi->bmiHeader.biSizeImage, &dwBytes, NULL );
    if ( !bRet || dwBytes != bi->bmiHeader.biSizeImage )
    {
        ::CloseHandle( hFile );
        goto err_exit;
    }

    ::CloseHandle( hFile );

    free( lpData );
    free( bi );
    return TRUE;

err_exit:
    free( lpData );
    free( bi );
    return FALSE;
}

BOOL CopyScreen( LPCTSTR lpszFile, WORD nBits = 24 )
{
    HDC hDC, hMemDC;
    HBITMAP hBitmap, hBitmapOld;
    int nWidth, nHeight;
    BOOL bRet;

    bRet = TRUE;

    hDC = ::GetDC( NULL );
    nWidth = ::GetSystemMetrics( SM_CXSCREEN );
    nHeight = ::GetSystemMetrics( SM_CYSCREEN );
    hMemDC = ::CreateCompatibleDC( hDC );
    hBitmap = ::CreateCompatibleBitmap( hDC, nWidth, nHeight );
    hBitmapOld = ( HBITMAP )::SelectObject( hMemDC, ( HGDIOBJ )hBitmap );

    bRet = ::BitBlt( hMemDC, 0, 0, nWidth, nHeight, hDC, 0, 0, SRCCOPY );
    if ( bRet )
    {
        bRet = BmpFromHandle( hMemDC, hBitmap, nBits, lpszFile );
    }

    ::SelectObject( hMemDC, ( HGDIOBJ )hBitmapOld );
    ::DeleteObject( ( HGDIOBJ )hBitmap );
    ::DeleteDC( hMemDC );
    ::ReleaseDC( NULL, hDC );
    return bRet;
}

BOOL CopyRC( UINT nBitmapID, LPCTSTR lpszFile, WORD nBits = 24 )
{
    HDC hDC;
    HBITMAP hBitmap;
    BOOL bRet;

    bRet = TRUE;

    hDC = ::GetDC( NULL );

    hBitmap = ::LoadBitmap( ::GetModuleHandle( NULL ), MAKEINTRESOURCE( nBitmapID ) );
    if ( hBitmap )
    {
        bRet = BmpFromHandle( hDC, hBitmap, nBits, lpszFile );
    }
    else
    {
        bRet = FALSE;
    }

    ::DeleteObject( ( HGDIOBJ )hBitmap );
    ::ReleaseDC( NULL, hDC );

    return bRet;
}