老师我遇到两个问题，帮忙看看，谢谢
1.获取不到子菜单的背景
2.获取的主菜单索引都为0.麻烦老师帮忙看看
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<a href="#" class="cate_datail_tit_lk">厨卫大电</a>
<i class="iconfont cate_datail_tit_arrow"></i>
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<a href="#" class="cate_datail_tit_lk">厨房小电</a>
<i class="iconfont cate_datail_tit_arrow"></i>
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<dd class="cate_detail_con">
<a href="#" class="cate_detail_con_lk">破壁机</a>
<a href="#" class="cate_detail_con_lk">电烤箱</a>
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<a href="#" class="cate_detail_con_lk">豆浆机</a>
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<a href="#" class="cate_detail_con_lk">咖啡机</a>
<a href="#" class="cate_detail_con_lk">电饼铛</a>
<a href="#" class="cate_detail_con_lk">榨汁机/原汁机</a>
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<a href="#" class="cate_detail_con_lk">微波炉</a>
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<a href="#" class="cate_detail_con_lk">面条机</a>
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<dt class="cate_detail_tit">
<a href="#" class="cate_datail_tit_lk">生活电器</a>
<i class="iconfont cate_datail_tit_arrow"></i>
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<dd class="cate_detail_con">
<a href="#" class="cate_detail_con_lk">取暖电器</a>
<a href="#" class="cate_detail_con_lk">加湿器</a>
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<dl class="cate_datail_item cate_datail_item8">
<dt class="cate_detail_tit">
<a href="#" class="cate_datail_tit_lk">个护健康</a>
<i class="iconfont cate_datail_tit_arrow"></i>
</dt>
<dd class="cate_detail_con">
<a href="#" class="cate_detail_con_lk">剃须刀</a>
<a href="#" class="cate_detail_con_lk">电动牙刷</a>
<a href="#" class="cate_detail_con_lk">电吹风</a>
<a href="#" class="cate_detail_con_lk">美容器</a>
<a href="#" class="cate_detail_con_lk">洁面仪</a>
<a href="#" class="cate_detail_con_lk">按摩器</a>
<a href="#" class="cate_detail_con_lk">健康秤</a>
<a href="#" class="cate_detail_con_lk">卷/直发器</a>
<a href="#" class="cate_detail_con_lk">剃/脱毛器</a>
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<a href="#" class="cate_detail_con_lk">足浴盆</a>
<a href="#" class="cate_detail_con_lk">足疗机</a>
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<dl class="cate_datail_item cate_datail_item9">
<dt class="cate_detail_tit">
<a href="#" class="cate_datail_tit_lk">视听影音</a>
<i class="iconfont cata_datail_tit_arrow"></i>
</dt>
<dd class="cate_detail_con">
<a href="#" class="cate_detail_con_lk">家庭影院</a>
<a href="#" class="cate_detail_con_lk">KTV影响</a>
<a href="#" class="cate_detail_con_lk">迷你音响</a>
<a href="#" class="cate_detail_con_lk">DVD</a>
<a href="#" class="cate_detail_con_lk">功效</a>
<a href="#" class="cate_detail_con_lk">回音壁</a>
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玩3C
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<a href="#" class="cate_channel_lk">
手机频道
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网上营业厅
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配件频道
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智能数码
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影像Club
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<dl class="cate_datail_item cate_datail_item1">
<dt class="cate_detail_tit">
<a href="#" class="cate_datail_tit_lk">手机通讯</a>
<i class="iconfont cate_datail_tit_arrow"></i>
</dt>
<dd class="cate_detail_con">
<a href="#" class="cate_detail_con_lk">手机</a>
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<a href="#" class="cate_detail_con_lk">老人机</a>
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<a href="#" class="cate_detail_con_lk">合约机</a>
<a href="#" class="cate_detail_con_lk">手机卡</a>
<a href="#" class="cate_detail_con_lk">宽带</a>
<a href="#" class="cate_detail_con_lk">充话费/流量</a>
<a href="#" class="cate_detail_con_lk">中国电信</a>
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<dl class="cate_datail_item cate_datail_item3">
<dt class="cate_detail_tit">
<a href="#" class="cate_datail_tit_lk">手机配件</a>
<i class="iconfont cate_datail_tit_arrow"></i>
</dt>
<dd class="cate_detail_con">
<a href="#" class="cate_detail_con_lk">手机壳</a>
<a href="#" class="cate_detail_con_lk">贴膜</a>
<a href="#" class="cate_detail_con_lk">手机存储卡</a>
<a href="#" class="cate_detail_con_lk">数据线</a>
<a href="#" class="cate_detail_con_lk">充电线</a>
<a href="#" class="cate_detail_con_lk">手机耳机</a>
<a href="#" class="cate_detail_con_lk">创意配件</a>
<a href="#" class="cate_detail_con_lk">手机饰品</a>
<a href="#" class="cate_detail_con_lk">手机电池</a>
<a href="#" class="cate_detail_con_lk">苹果周边</a>
<a href="#" class="cate_detail_con_lk">移动电源</a>
<a href="#" class="cate_detail_con_lk">蓝牙耳机</a>
<a href="#" class="cate_detail_con_lk">手机支架</a>
<a href="#" class="cate_detail_con_lk">车载配件</a>
<a href="#" class="cate_detail_con_lk">拍照配件</a>
</dd>
</dl>
<dl class="cate_datail_item cate_datail_item4">
<dt class="cate_detail_tit">
<a href="#" class="cate_datail_tit_lk">摄影摄像</a>
<i class="iconfont cate_datail_tit_arrow"></i>
</dt>
<dd class="cate_detail_con">
<a href="#" class="cate_detail_con_lk">数码相机</a>
<a href="#" class="cate_detail_con_lk">微单相机</a>
<a href="#" class="cate_detail_con_lk">单反相机</a>
<a href="#" class="cate_detail_con_lk">拍立得</a>
<a href="#" class="cate_detail_con_lk">运动相机</a>
<a href="#" class="cate_detail_con_lk">摄像机</a>
<a href="#" class="cate_detail_con_lk">镜头</a>
<a href="#" class="cate_detail_con_lk">户外器材</a>
<a href="#" class="cate_detail_con_lk">影棚器材</a>
<a href="#" class="cate_detail_con_lk">冲印服务</a>
<a href="#" class="cate_detail_con_lk">数码相框</a>
</dd>
</dl>
<dl class="cate_datail_item cate_datail_item5">
<dt class="cate_detail_tit">
<a href="#" class="cate_datail_tit_lk">数码配件</a>
<i class="iconfont cate_datail_tit_arrow"></i>
</dt>
<dd class="cate_detail_con">
<a href="#" class="cate_detail_con_lk">存储卡</a>
<a href="#" class="cate_detail_con_lk">三脚架/云台</a>
<a href="#" class="cate_detail_con_lk">相机包</a>
<a href="#" class="cate_detail_con_lk">滤镜</a>
<a href="#" class="cate_detail_con_lk">闪光灯/手柄</a>
<a href="#" class="cate_detail_con_lk">相机清洁/贴膜</a>
<a href="#" class="cate_detail_con_lk">机身附件</a>
<a href="#" class="cate_detail_con_lk">镜头附件</a>
<a href="#" class="cate_detail_con_lk">读卡器</a>
<a href="#" class="cate_detail_con_lk">支架</a>
<a href="#" class="cate_detail_con_lk">电池/充电器</a>
</dd>
</dl>
<dl class="cate_datail_item cate_datail_item6">
<dt class="cate_detail_tit">
<a href="#" class="cate_datail_tit_lk">影音娱乐</a>
<i class="iconfont cate_datail_tit_arrow"></i>
</dt>
<dd class="cate_detail_con">
<a href="#" class="cate_detail_con_lk">耳机/耳麦</a>
<a href="#" class="cate_detail_con_lk">音箱/音响</a>
<a href="#" class="cate_detail_con_lk">智能音箱</a>
<a href="#" class="cate_detail_con_lk">便携/无线音箱</a>
<a href="#" class="cate_detail_con_lk">收音机</a>
<a href="#" class="cate_detail_con_lk">麦克风</a>
<a href="#" class="cate_detail_con_lk">MP3/MP4</a>
<a href="#" class="cate_detail_con_lk">专业音频</a>
<a href="#" class="cate_detail_con_lk">音频线</a>
</dd>
</dl>
<dl class="cate_datail_item cate_datail_item7">
<dt class="cate_detail_tit">
<a href="#" class="cate_datail_tit_lk">智能设备</a>
<i class="iconfont cate_datail_tit_arrow"></i>
</dt>
<dd class="cate_detail_con">
<a href="#" class="cate_detail_con_lk">智能手环</a>
<a href="#" class="cate_detail_con_lk">智能手表</a>
<a href="#" class="cate_detail_con_lk">智能眼镜</a>
<a href="#" class="cate_detail_con_lk">智能机器人</a>
<a href="#" class="cate_detail_con_lk">运动跟踪器</a>
<a href="#" class="cate_detail_con_lk">健康监测</a>
<a href="#" class="cate_detail_con_lk">智能配饰</a>
<a href="#" class="cate_detail_con_lk">智能家居</a>
<a href="#" class="cate_detail_con_lk">体感车</a>
<a href="#" class="cate_detail_con_lk">无人机</a>
</dd>
</dl>
<dl class="cate_datail_item cate_datail_item8">
<dt class="cate_detail_tit">
<a href="#" class="cate_datail_tit_lk">电子教育</a>
<i class="iconfont cate_datail_tit_arrow"></i>
</dt>
<dd class="cate_detail_con">
<a href="#" class="cate_detail_con_lk">学生平板</a>
<a href="#" class="cate_detail_con_lk">点读机/笔</a>
<a href="#" class="cate_detail_con_lk">早教益智</a>
<a href="#" class="cate_detail_con_lk">录音笔</a>
<a href="#" class="cate_detail_con_lk">电纸书</a>
<a href="#" class="cate_detail_con_lk">电子词典</a>
<a href="#" class="cate_detail_con_lk">复读机</a>
<a href="#" class="cate_detail_con_lk">翻译机</a>
</dd>
</dl>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
<div class="fs_col2"></div>
<script src="script7.js"></script>
</body>
</html>
*{
margin: 0;
padding: 0;
}
@font-face {
font-family: 'iconfont';
src: url('font/iconfont.eot');
src: url('font/iconfont.eot?#iefix') format('embedded-opentype'),
url('font/iconfont.woff2') format('woff2'),
url('font/iconfont.woff') format('woff'),
url('font/iconfont.ttf') format('truetype'),
url('font/iconfont.svg#iconfont') format('svg');
}
body{
webkit-font-smoothing: antialiased;
background-color: #fff;
font: 12px/1.5 Microsoft YaHei,tahoma,arial,Hiragino Sans GB,\\5b8b\4f53,sans-serif;
color: #666;
}
.fs_coll{
float: left;
height: 480px;
width: 190px;
margin-right: 10px;
}
.cate{
position: relative;
z-index: 3;
}
.cate_menu{
overflow: hidden;
padding: 10px 0;
height: 450px;
/* background-color: #fefefe;*/
background-color: #ffb6c1;
color: #636363;
margin-top: 10px;
}
.cate_menu_item{
overflow: hidden;
padding-left: 18px;
height: 25px;
line-height: 25px;
}
a{
color: #666;
text-decoration: none;
}
li{
list-style: none;
}
.cate_menu_lk{
font-size: 14px;
color: #333;
transition: color .2s ease;
}
.cate_menu_line{
padding: 0 2px;
font-size: 12px;
}
.cate_pop{
position: absolute;
left: 191px;
top: 0;
width: 998px;
min-height: 468px;
border: 1px solid #f7f7f7;
background-color: #fff;
box-shadow: 2px 0 5px rgba(0,0,0,.3);
}
.cate_part{
display: none;
padding: 20px 0 10px;
}
.cate_part_col1{
float: left;
width: 800px;
}
.cate_channel{
overflow: hidden;
padding-left: 20px;
height: 24px;
}
.cate_channel_lk{
float: left;
margin-right: 10px;
padding: 0 10px;
height: 24px;
background-color: #333;
line-height: 24px;
text-align:center;
color: #fff;
}
.icofont{
font-family: iconfont,sans-serif;
font-style: normal;
font-size: 13px;
}
.iconfont {
font-family: iconfont,sans-serif;
font-style: normal;
}
.cate_detail{
overflow: hidden;
padding: 10px 0 0 20px;
}
.cate_datail_item{
position: relative;
padding-left: 80px;
}
.cate_detail_tit{
overflow: hidden;
position: absolute;
left: 0;
top: 6px;
width: 70px;
text-align: right;
font-weight: 700;
white-space: nowrap;
text-overflow: ellipsis;
}
.cate_datail_tit_lk{
color: #333;
font-weight: 700;
}
.cate_detail_con{
overflow: hidden;
padding: 5px 0;
}
.cate_detail_con_lk{
float: left;
margin: 3px 0;
padding: 0 7px;
height: 16px;
line-height: 16px;
white-space: nowrap;
}
.cate_promotion{
margin: 10px auto 0;
width: 168px;
}
.cate_promotion_lk{
display: block;
margin-bottom: 1px;
height: 134px;
background-color: #e7e7e7;
}
img{
border: 0;
vertical-align: middle;
}
.cate_part_col2{
float: left;
width: 198px;
}
.cate_brand{
margin: auto;
width: 168px;
font-size: 0;
}
.cate_brand_lk{
overflow: hidden;
display: inline-block;
width: 83px;
height: 35px;
margin: 0 0 1px 1px;
background-color: #e7e7e7;
}
.cate_menu_item:hover .cate_pop{
display: block;
}
var jCate = byId("J_cate"),
menuItems = jCate.getElementsByClassName("cate_menu"),
jpoctn =byId("J_popCtn");
function addHandler(element, type, handler) {
if (element.addEventListener) {
element.addEventListener(type, handler, true);
}
else if (element.attachEvent) {
element.attachEvent('on' + type, handler);
}
else {
element['on' + type] = handler;
}
}
function byId(id){
return typeof (id)==="string" ? document.getElementById(id):id;
}
//鼠标滑过主菜单
for (var m = 0,idx,mlen =menuItems.length;m<mlen;m++){
//给所有主菜单定义属性，标明它的索引
menuItems[m].setAttribute("data-index",m)
addHandler(menuItems[m],"mouseover",function () {
//显示主菜单所在背景
jpoctn.className ="Js_popCtn";
//获取当前主菜单的索引
idx = this.getAttribute("data-index");
alert(idx);
})
}
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