<ul class="topMenu">
     <li class="topMenu">
        <a href="__APP__/Contact" onmouseout="MM_swapImgRestore()" onmouseover="MM_swapImage('Image16','','../Public/images/menu/contact2.jpg',1)"><img src="../Public/images/menu/contact.jpg" alt="contact us" name="Image16" id="Image16" /></a>
        </li>
        <li class="topMenu">
        <a href="__APP__/Service" onmouseout="MM_swapImgRestore()" onmouseover="MM_swapImage('Image19','','../Public/images/menu/service2.jpg',1)"><img src="../Public/images/menu/service.jpg" alt="service" name="Image19" id="Image19" /></a> 
        </li>
     <li class="topMenu">
        <a href="__APP__/Product" onmouseout="MM_swapImgRestore()" onmouseover="MM_swapImage('Image17','','../Public/images/menu/products2.gif',1)"><img src="../Public/images/menu/products.jpg" alt="products" name="Image17" id="Image17" /></a>    </ul>
菜单是用js来控制,当鼠标hover和out时加载图片改变菜单效果 。但是不知道怎么让鼠标点击后也达到鼠标hover时的效果?