C / C++ / MFC

CPoint CDC::SetViewportOrg(int x, int y)<br />
{<br />
	ASSERT(m_hDC != NULL);<br />
	CPoint point;<br />
<br />
	if (m_hDC != m_hAttribDC)<br />
		VERIFY(::SetViewportOrgEx(m_hDC, x, y, &point));<br />
	if (m_hAttribDC != NULL)<br />
		VERIFY(::SetViewportOrgEx(m_hAttribDC, x, y, &point));<br />
	return point;               <<<<<<<<<<<<<<<<Here stops the debugger !!!???<br />
}

int WINAPI PaintSpecialGraphics(HDC hDC);

int WINAPI PaintSpecialGraphics(HDC hDC)
{
    CDC dc;
    dc.Attach(hDC);
    // Do stuff with 'dc' here...
    dc.Detach();
}

CPaintDC dc(this);
PaintSpecialGraphics(dc);

Stephen Hewitt wrote:

I suspect you can't use MFC classes across DLL boundries. Here are some possible reasons:
- MFC's handle map implementation.
- Different heaps.
- Different compiler settings in EXE and DLL.

class CExample
{
public:
    int GetNum() { return g_Number; }
}

Zac Howland wrote:

First, using operations like CreateWindow in your constructor is dangerous since if CreateWindow fails, you have not completed your construction of the object. It is safer to initialize any variables and have a separate Create function to create your window.

Zac Howland wrote:

Doing this as part of the static memory allocation for your Dll can cause problems if the DLL fails to load properly. Basically, the same arguments for not calling CreateWindow inside your DllMain apply to calling it before it gets called as well.

Nader Elshehabi wrote:

char* MyText = new char;
cin>>MyText;
delete[] MyText;

void main()
{
	char* MyText = new char;
	cin>>MyText;
	delete MyText;
}

void main()
{
	char* MyText = new char[100];
	cin>>MyText;
	delete [] MyText;
}