Question

怎么只用Jquery实现菜单的收缩，点一下把子菜单隐藏，再点一下把子菜单展开，就像QQ好友分类那样，3Q！

<div class="main">
<div class="left">
<div class="toptit"><img src="images/icon01.gif" width="63" height="54" />系统管理</div>
<div class="list">
<ul>
<li class="nav01"><a href="#">按钮名称</a></li>
<li class="li01">
<ul>
<li><a href="#">按钮名称</a></li>
<li><a href="#">按钮名称</a></li>
<li><a href="#">按钮名称</a></li>
<li><a href="#">按钮名称</a></li>
</ul>
</li>
</ul>

Answer 1

$(function(){

$("#a").click(function(){
$('#b').toggle();
});

});

Answer 2

<script type="text/javascript" src="./jquery-1.4.2.min.js"></script>
<script type="text/javascript">
$(document).ready(function(){
$(".nav01").toggle(
function(){
$(".li01").children('ul').hide();
},
function(){
$(".li01").children('ul').show();
}
);
});
</script>