[c++] VC基本概念

 1 void CMFCApplication3Dlg::DrawCircle(CDC *pDC,CRect &rectPicture,double x1, double y1, double x2, double y2,color a)
 2 {
 3     // TODO: 在此添加控件通知处理程序代码
 4     CPen newPen;
 5     CPen *pOldPen;
 6     
 7     newPen.CreatePen(PS_SOLID, 3, RGB(a.r,a.g,a.b));
 8     pOldPen = pDC->SelectObject(&newPen);
 9     pDC->SelectStockObject(NULL_BRUSH);
10     pDC->Ellipse(x1, y1, x2, y2);
11     //pDC->MoveTo(rectPicture.left, rectPicture.bottom);
12     //pDC->LineTo(rectPicture.left + 50, rectPicture.bottom - 100);
13     pDC->SelectObject(pOldPen);
14     newPen.DeleteObject();
15 }