C / C++ / MFC

class CPolygon {
  protected:
    int width, height;
  public:
    void set_values (int a, int b)
      { width=a; height=b; }
    //virtual int area (void) =0;
    virtual int area (void) 
      {return 0;}
    void printarea (void)
      { cout << this->area() << endl; }
  };
class CTriangle: public CPolygon {
  public:
    int area (void)
      { return (width * height / 2); }
    int testdata;
  };

int main () {
  CPolygon poly;
  CTriangle trgl;
  CPolygon * ppoly2 = &trgl;
  CTriangle * ptrgl = (CTriangle *) &poly;
  ppoly2->set_values (4,5);
  ptrgl->set_values (4,5);
  ppoly2->printarea();
  ptrgl->printarea();
  ptrgl->testdata = 100;
  cout << ppoly1->area() << endl;
  cout << ppoly2->area() << endl;
  cout << ptrgl->area() << endl;
  cout << ptrgl->testdata << endl;
  system("PAUSE");
  return EXIT_SUCCESS;
}

BOOL CALLBACK CMFCTesterDlg::EnumWindowsProc(HWND hwnd, LPARAM lParam)
{
	if(hwnd == ::FindWindow(NULL, L"Untitled - Notepad"))
	{
		CMFCTesterDlg *pThis = (CMFCTesterDlg *)lParam;
		HWND hwnddest = *pThis;

		RECT rect;
		::GetWindowRect(hwnd, &rect);
		HDC dc = ::GetDCEx(hwnd, NULL, DCX_WINDOW);
		HDC destdc = ::GetDC(hwnddest);
		::BitBlt(destdc, 0, 0, rect.right-rect.left, rect.bottom-rect.top, dc, 0, 0, SRCCOPY);
		::ReleaseDC(hwnddest, destdc);
		::ReleaseDC(hwnd, dc);
	};
	return TRUE;
}


void CMFCTesterDlg::OnOK()
{
	::EnumWindows(&CMFCTesterDlg::EnumWindowsProc, (LPARAM)this);	
}

Mark Salsbery
Microsoft MVP - Visual C++

robertaallan wrote:

...will it expire or maybe die on me in the near future.