Re: How to export my memDC to a *.bmp file directly

Hi Ray,

u do it so:

greetings and regards,
 Karsten Schulz
(www.kahnsoft.de)

BITMAP bitmap;
  if(!::GetObject ((HBITMAP)hBmp, sizeof (bitmap), &bitmap))
 return false;

  if(!bitmap.bmBits)
    return false; //ur HBITMAP has not a DibSection
SelectObject( &CBitmap::m_mymember) u must do

  PBITMAPINFO pBitmapInfo = (BITMAPINFO*)(new
char[sizeof(BITMAPINFOHEADER)+(bitmap.bmBitsPixel==8?256:1)*sizeof(RGBQUAD)]);
  if(!pBitmapInfo)
    return false;

  m_pBitmapInfo->bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
  m_pBitmapInfo->bmiHeader.biWidth = (m_srcw=bitmap.bmWidth);
  m_pBitmapInfo->bmiHeader.biHeight =
(m_srch=bitmap.bmHeight);//botomup
  m_pBitmapInfo->bmiHeader.biPlanes = bitmap.bmPlanes;
  m_pBitmapInfo->bmiHeader.biBitCount = bitmap.bmBitsPixel;
  m_pBitmapInfo->bmiHeader.biCompression = BI_RGB;
  m_pBitmapInfo->bmiHeader.biSizeImage =
(bitmap.bmWidth*bitmap.bmHeight*(bitmap.bmBitsPixel>>3));
  m_pBitmapInfo->bmiHeader.biXPelsPerMeter = 0;
  m_pBitmapInfo->bmiHeader.biYPelsPerMeter = 0;
  m_pBitmapInfo->bmiHeader.biClrUsed = bitmap.bmBitsPixel==8?256:0;
  m_pBitmapInfo->bmiHeader.biClrImportant = 0;

Save("c:\\otto.bmp",bitmap.bmBits);

//save a bmp file from Dib
bool CDib::Save(LPCSTR fname,LPVOID pMem)
{
   CString path(fname);

   if(path.IsEmpty())
     return false;

   HANDLE hf;
   BITMAPFILEHEADER hdr;

   int tmp;

   hf = CreateFile(path.GetBuffer(0),
                   GENERIC_READ | GENERIC_WRITE,
                   (DWORD) 0,
                   (LPSECURITY_ATTRIBUTES) NULL,
                   CREATE_ALWAYS,
                   FILE_ATTRIBUTE_NORMAL,
                   (HANDLE) NULL);

    if (hf == INVALID_HANDLE_VALUE)
       return false;

    hdr.bfType = 0x4d42;
    hdr.bfSize = (DWORD) (sizeof(BITMAPFILEHEADER) +
m_pBitmapInfo->bmiHeader.biSize + m_pBitmapInfo->bmiHeader.biClrUsed *
                          sizeof(RGBQUAD) +
m_pBitmapInfo->bmiHeader.biSizeImage);
    hdr.bfReserved1 = 0;
    hdr.bfReserved2 = 0;
    hdr.bfOffBits = (DWORD) sizeof(BITMAPFILEHEADER) +
                    m_pBitmapInfo->bmiHeader.biSize +
m_pBitmapInfo->bmiHeader.biClrUsed * sizeof (RGBQUAD);

    if(!WriteFile(hf, (LPVOID) &hdr, sizeof(BITMAPFILEHEADER),(LPDWORD)
&tmp, (LPOVERLAPPED) NULL))
    {
      CloseHandle(hf);
   return false;
    }

    if(!WriteFile(hf, (LPVOID) &m_pBitmapInfo->bmiHeader,
sizeof(BITMAPINFOHEADER) + m_pBitmapInfo->bmiHeader.biClrUsed * sizeof
(RGBQUAD),(LPDWORD) &tmp, (LPOVERLAPPED) NULL))
    {
       CloseHandle(hf);
    return false;
    }

    if(!WriteFile(hf, (LPCVOID) pMem,
m_pBitmapInfo->bmiHeader.biSizeImage,(LPDWORD) &tmp, (LPOVERLAPPED) NULL) )
    {
       CloseHandle(hf);
    return false;
    }

    CloseHandle(hf);

 return true;
}

"Ray" <rguan@trafficcast.com.cn> schrieb im Newsbeitrag
news:8F643D10-C5CD-4B68-8F00-001D166DD9EA@microsoft.com...