设置默认选中一个单选按钮，OnInitDialog()函数中添加:
CheckRadioButton(IDC_RADIO1, IDC_RADIO2, IDC_RADIO2);
按钮事件处理
1 void CMFCApplication3Dlg::OnBnClickedChkBlue() 2 { 3 // 选中蓝色让对话框失效，触发清除背景 4 Invalidate(); 5 } 6 7 void CMFCApplication3Dlg::OnBnClickedChkRed() 8 { 9 OnBnClickedChkBlue(); 10 } 11 12 void CMFCApplication3Dlg::OnBnClickedChkGreen() 13 { 14 OnBnClickedChkBlue(); 15 } 16 17 void CMFCApplication3Dlg::OnBnClickedRadio1() 18 { 19 OnBnClickedChkBlue(); 20 } 21 22 //清除背景时画图 23 BOOL CMFCApplication3Dlg::OnEraseBkgnd(CDC* pDC) 24 { 25 // TODO: 在此添加消息处理程序代码和/或调用默认值 26 BOOL bRet = CDialogEx::OnEraseBkgnd(pDC); 27 int nRed, nGreen, nBlue; 28 nRed = m_chk_red.GetCheck() ? 255 : 0; 29 nGreen = m_chk_green.GetCheck() ? 255 : 0; 30 nBlue = m_chk_blue.GetCheck() ? 255 : 0; 31 32 COLORREF crFore = RGB(nRed, nGreen, nBlue); 33 CBrush brush; 34 brush.CreateSolidBrush(crFore); 35 CBrush *pOldBrush = pDC->SelectObject(&brush); 36 37 RECT rc = { 50,20,150,120 }; 38 if (m_rd_rect.GetCheck()) { 39 pDC->Rectangle(&rc); 40 } 41 else { 42 pDC->Ellipse(&rc); 43 } 44 pDC->SelectObject(pOldBrush); 45 46 return bRet; 47 }