Advanced MFC Programming

Chapter 9. Font
Still, we need to display the result in function CView::OnDraw(…). In the sample, this function is
implemented as follows:
void CGDIView::OnDraw(CDC* pDC)
{
CGDIDoc *pDoc=GetDocument();
ASSERT_VALID(pDoc);
CString szStr;
int nYPos;
nYPos=10;
szStr.Format("Number of raster fonts: %d", m_nFontCount[0]);
pDC->TextOut(10, nYPos, szStr);
nYPos+=20;
szStr.Format("Number of vector fonts: %d", m_nFontCount[1]);
pDC->TextOut(10, nYPos, szStr);
nYPos+=20;
}
szStr.Format("Number of TrueType fonts: %d", m_nFontCount[2]);
pDC->TextOut(10, nYPos, szStr);
nYPos+=20;
We just display three lines of text indicating how many fonts are contained in the system for each
different font family.
Enumerating Font
Apart from the above information (how many fonts there are for each font family), we may further
want to know the exact properties of every font type (i.e., face name). To implement this, we need to
allocate enough memory to store the information of all fonts. Here, the size of this buffer depends on the
number of fonts whose properties are to be retrieved. Since each font need a LOGFONT structure to store all
its information, we can use the following formulae to calculate the required buffer size:
(sizeof structure LOGFONT) × (number of fonts)
For this purpose, in the sample, another two variables are declared in class CGDIView as follows:
……
……
class CGDIView : public CScrollView
{
protected:
}
LPLOGFONT m_lpLf[3];
CFont *m_ptrFont;
Array m_lpLf will be used to store LOGFONT information, and m_ptrFont will be used to store CFont
type variables. The variables are initialized in the constructor as follows:
……
CGDIView::CGDIView()
{
}
m_lpLf[0]=m_lpLf[1]=m_lpLf[2]=NULL;
m_ptrFont=NULL;
We need to provide another callback function to retrieve the actual information for each font type. In
the sample, this callback function is declared and implemented as follows:
int CALLBACK EnumFontProc(LPLOGFONT, LPNEWTEXTMETRIC, DWORD, LPVOID);
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