点击单选框使按钮灰化

//WM_CREATE消息里创建：
::CreateWindowEx(0, "button", "radio button", WS_CHILD|WS_VISIBLE|BS_RADIOBUTTON,50, 350, 110, 30, hwnd, (HMENU)ID_RADIO, GetModuleHandle(NULL), NULL);
//选中时响应
       case ID_RADIO:
            {
            // 是否选中单选按钮
            BOOL bChecked = ::IsDlgButtonChecked(hwnd, ID_RADIO);
            // 设置按钮ID为ID_OK的有效状态 这里是无效 即灰化
            ::EnableWindow(::GetDlgItem(hwnd, ID_OK), bChecked);
            // 设置本控件状态
            ::CheckDlgButton(hwnd, ID_RADIO, !bChecked);
            }