MapX的滚轮消息//用什么函数直接放大与缩小

这种方法只能调用出来+号放大镜与-号放大镜//不能直接放大

 BOOL COtdrClientView::PreTranslateMessage(MSG* pMsg)
{
// TODO: 在此添加专用代码和/或调用基类
if(pMsg->message==WM_MOUSEWHEEL)
{
         short zDelta = HIWORD(pMsg->wParam);
 if(zDelta == 120)
m_ctrlMapX.SetCurrentTool(miZoomInTool);//放大标示 miZoomInTool 
 else if(zDelta == -120)
m_ctrlMapX.SetCurrentTool(miZoomOutTool);//缩小标示 miZoomOutTool 
 return 1;
}
return CView::PreTranslateMessage(pMsg);
}
//-------------

//这种方法没效果啊!
 BOOL COtdrClientView::PreTranslateMessage(MSG* pMsg)
{
// TODO: 在此添加专用代码和/或调用基类
if(pMsg->message==WM_MOUSEWHEEL)
{
     m_ctrlMapX.SetMousewheelSupport(miFullMousewheelSupport); 
     return 1;
}
return CView::PreTranslateMessage(pMsg);
}

[解决办法]
mapx 有一个mousewheelsupport属性