js顶部可以伸缩的导航菜单效果
分类：实例代码
本章节分享一段代码实例，它实现了顶部可以伸缩的导航菜单效果。
本来代码里面有图片之类的，但是为了简便都省略了，所以测试的时候注意一下。
代码实例如下:
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<meta name="author" content="http://www.pipipi.net/" />
<title>前端教程网</title>
<style>
html,body{
margin:0;
}
ha{
margin:0 auto;
}
#fx_topToolbar{
position:relative;
op:-76px;
left:0;
margin:0 auto;
height:92px;
background:#0C3E74;
width:700px;
text-align:center;
}
#fx_topToolbar .shell{
margin:0 auto;
padding:13px 0;
}
#btn_offOn{
position:absolute;
bottom:-8px;
left:20px;
height:24px;
width:150px;
}
#btn_offOn a{
display:block;
zoom:1;
height:24px;
position:relative;
right:-16px;
}
</style>
<script>
(JS={
$:function(o){
return typeof o=="string"?document.getElementById(o):o
},
on:function(o,type,fn){
o.attachEvent?o.attachEvent('on'+type,function(){fn.call(o)}):o.addEventListener(type,fn,false);
return JS.on
},
move:function(who,attr,val,s,fn){
var fm=parseInt(who.style)||0;
clearInterval(who['timer_'+attr]);
var iFx=(function(form,to,s){
return function (){
return form+=Math[form<to?'ceil':'floor']((to-form)*(s||0.3))
};
})(fm,val,s);
who['timer_'+attr]=setInterval(function (){
var v=iFx();
who.style=v+'px';
if(v==val){
fn&&fn.call(who);clearInterval(who['timer_'+attr]);
};
},18);
}
}).on(window,'load',function (){
var Q=JS.$('fx_topToolbar');
Q.style.top='-74px';
JS.on(JS.$('btn_offOn'),'mouseover',function(){JS.move(Q,'top',0)})
(Q,'mouseout',function (){Q.outTimer=setTimeout(function(){JS.move(Q,'top',-74)},10)})
(Q,'mouseover',function (){clearTimeout(this.outTimer)});
})
</script>
</head>
<body>
<div id="fx_topToolbar">
<div class="shell">
<a href="#" title=""></a>
<a href="#" title=""></a>
</div>
<div id="btn_offOn"><a href="#" title=""></a></div>
</div>
</body>
</html>