0 bytes CImage saved

[_Flaviu]

I intend to save CBitmap into a bmp file, here is the code:

// MyDocument.cpp
CMyView* pView = (CMyView*)GetNextView(pos);
CDC* pDC = pView->GetDC();

		CDC MemDC;
		MemDC.CreateCompatibleDC(pDC);

		CBitmap bitmap;
		bitmap.CreateCompatibleBitmap(pDC, GetTotalCx(), GetTotalCy());
		CBitmap\* pOldBitmap = (CBitmap\*)MemDC.SelectObject(&bitmap);
		// draw the MemDC
		pDC->BitBlt(0, 0, GetTotalCx(), GetTotalCy(), &MemDC, 0, 0, SRCCOPY);
		CBitmap\* pFinalBitmap = (CBitmap\*)MemDC.SelectObject(pOldBitmap);
		CImage Image;
		Image.Attach((HBITMAP)pFinalBitmap->m\_hObject);
		Image.Save(ar.GetFile()->GetFileName(), Gdiplus::ImageFormatBMP);
		bitmap.DeleteObject();

but the resulting bitmap file has 0 bytes ... why ? Could you help me ?

[CPallini]

How are defined GetTotalCx, GetTotalCy?

[_Flaviu]

They have the bitmap sizes, and they have valid values: 1400X1000. (I verified that). P.S. Moreover, if I put this code on OnDraw handler, is drawing well.

[_Flaviu]

Seem to go now, I overload CDocument::DoSave(LPCTSTR lpszPathName, BOOL bReplace), and I put there the saving code ... In case that everyone need it. Thank you for all support.

[Jochen Arndt]

I don't think that it is the source of your problem, but there is an error in your code: You are deleting the CBitmap while it is still attached to the CImage. So you should detach first or use CImage::Destroy which will detach and delete the bitmap. You should also check the return value of the Save function.

[_Flaviu]

CDC* pDC = pView->GetDC();
int nSaveDC = pDC->SaveDC();

CDC MemDC;
MemDC.CreateCompatibleDC(pDC);

CBitmap bitmap;
bitmap.CreateCompatibleBitmap(pDC, GetTotalCx(), GetTotalCy());
CBitmap\* pOldBitmap = (CBitmap\*)MemDC.SelectObject(&bitmap);
// draw MemDC
pDC->BitBlt(0, 0, GetTotalCx(), GetTotalCy(), &MemDC, 0, 0, SRCCOPY);
CBitmap\* pFinalBitmap = (CBitmap\*)MemDC.SelectObject(pOldBitmap);
CImage Image;
Image.Attach((HBITMAP)pFinalBitmap->m\_hObject);
Image.Save(lpszPathName, Gdiplus::ImageFormatBMP);
Image.Detach();
pDC->RestoreDC(nSaveDC);
bitmap.DeleteObject();

Here is the new code ... but strange, CImage::Save return 0... it is OK ? The saved image looks good ...

[Jochen Arndt]

CImage::Save returns a HRESULT where zero indicates success.

[_Flaviu]

Ahh, yes, you are right. Thank you.