http://msdn.microsoft.com/en-us/library/azz5wt61(v=vs.80).aspxA device context is a Windows data structure containing information about the drawing attributes of a device such as a display or a printer. All drawing calls are made through a device-context object, which encapsulates the Windows APIs f Read More
//filename:Hello.hclass CMyApp:public CWinApp{public: virtual BOOL InitInstance();};class CMainWindow:public CFrameWnd{public: CMainWindow();protected: afx_msg void OnPaint(); afx_msg void OnLButtonDown( UINT nFlags, CPoint point ); DECLARE_MESSAGE_MAP()};//filename:Hello.cpp#include <afxwin.h> Read More
#include <iostream>using namespace std;class P{public: P * m_p; P(){ this->m_p=this; } virtual void Intro(){ cout<<"this is P"<<endl; }};class S:public P{public : virtual void Intro(){ cout<<"this is S"<<endl; }};S s;int main(){ s.Intro(); s.m_p-& Read More