Article: Q149341
Product(s): Microsoft C Compiler
Version(s): winnt:4.0,4.1
Operating System(s):
Keyword(s): kbprint kbFont kbMFC kbPrinting kbVC400 kbVC410 kbDSupport kbGrpDSMFCATL kbNoUpdate
Last Modified: 11-SEP-2001
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The information in this article applies to:
- The Microsoft Foundation Classes (MFC), included with:
- Microsoft Visual C++, 32-bit Editions, versions 4.0, 4.1
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SYMPTOMS
========
Calling CFont::CreatePointFont() results in a font displayed in print preview
mode that is not of the point size requested.
CAUSE
=====
The CDC class contains two member variables for its current device context,
m_hDC and m_hAttribDC. m_hDC (the output device context) is equal to m_hAttribDC
(the attribute device context) by default. However, when print preview is
active, these two variables will not be equal; at that point, the m_hDC contains
the screen's device context and m_hAttribDC contains the printer's device
context.
The implementation of CreatePointFont() looks at the m_hDC member of the CDC
class to calculate the proper size for the font rather than the m_hAttribDC
member. The result of this behavior is that CreatePointFont will always create a
font sized for the screen device context.
RESOLUTION
==========
The following sample code works around the problem by creating another CDC
object based on the m_hAttribDC member of the original CDC and uses this new CDC
to call CFont::CreatePointFont().
Sample Code
-----------
/* Compile options needed: default
*/
void CMyView::OnDraw(CDC* pDC)
{
// dcPrinter's m_hDC and m_hAttribDC member variables
// will both be properly pointing to the printer DC.
CDC dcPrinter;
dcPrinter.Attach(pDC->m_hAttribDC);
CFont font;
font.CreatePointFont(110, "Courier New", &dcPrinter);
// You must detach from the DC after using
// our temporary dcPrinter object or problems will occur!
dcPrinter.Detach();
CFont* pOldFont = pDC->SelectObject(&font);
// Use font here...
pDC->SelectObject(pOldFont);
}
STATUS
======
Microsoft has confirmed this to be a bug in the Microsoft products listed at the
beginning of this article. This bug was corrected in Visual C++ 32- bit Edition
version 4.2.
Additional query words: 4.00 4.10 4.20 vcfixlist420
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Keywords : kbprint kbFont kbMFC kbPrinting kbVC400 kbVC410 kbDSupport kbGrpDSMFCATL kbNoUpdate
Technology : kbAudDeveloper kbMFC
Version : winnt:4.0,4.1
Issue type : kbbug
Solution Type : kbfix
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