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saving the content of a CDC to a bmp

snow_master asked
ca someone please post a code example of creating a CDC, writing stuff to it like .TextOut and then extracting all the data from that dc to save it as a bmp image ?
thanks in advance.
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To do this, you need to create a CBitmap object and select it into the CDC.  You need to do this before any of the drawing it done.  Then, do all of your drawing, TextOut, etc.  Finally, select the bitmap back out of the CDC and you have bitmap of what was drawn.

CDC * pDC;  // if you are doing this in the Paint function, you should get a CDC passed to you.  Otherwise you can create a CDC from a window.
int height = 640, width = 480;  // whatever size you actually want.

CBitmap  bmpTmp;
CBitmap * bmpOld = bmpTmp.CreateCompatibleBitmap(pDC, height, width);  // use this to select back after we're done.
... now do all the drawing you want...
CBitmap * bmpOut = pDC->SelectObject(bmpOld);
If you are ready to use COM then best way IMHO and shortest is:

BOOL SaveBitmap( LPCSTR lpFileName, HBITMAP hBitmap, HPALETTE hPal = NULL )
   BOOL bResult = FALSE;

   PICTDESC stPictDesc;
   stPictDesc.cbSizeofstruct = sizeof(PICTDESC);
   stPictDesc.picType = PICTYPE_BITMAP;
   stPictDesc.bmp.hbitmap = hBitmap;
   stPictDesc.bmp.hpal = hPal;

   LPPICTURE pPicture;
   HRESULT hr = OleCreatePictureIndirect( &stPictDesc, IID_IPicture, FALSE, reinterpret_cast<void**>(&pPicture) );
   if ( SUCCEEDED(hr) )
      LPSTREAM pStream;
      hr = CreateStreamOnHGlobal( NULL, TRUE, &pStream );
      if ( SUCCEEDED(hr) )
         long lBytesStreamed = 0;
         hr = pPicture->SaveAsFile( pStream, TRUE, &lBytesStreamed );
         if ( SUCCEEDED(hr) )
            HANDLE hFile = CreateFile( lpFileName,
                                       NULL );
            if ( hFile )
               HGLOBAL hMem = NULL;
               GetHGlobalFromStream( pStream, &hMem );
               LPVOID lpData = GlobalLock( hMem );

               DWORD dwBytesWritten;
               bResult = WriteFile( hFile, lpData, lBytesStreamed, &dwBytesWritten, NULL );
               bResult &= ( dwBytesWritten == (DWORD)lBytesStreamed );

               // clean up
         // clean up        
      // clean up      

   return bResult;  

So you see it does not require a lot of code just one simple function.
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Split between DarthPedro, jacobkristensen  and  gelbert
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