JS 菜单收拉样式

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script>
//想将getElementById()方法 改为getElementsByName(),在把<div 中的id 全部换成name> 为什么不能触发点击事件?
        function on_Click_1() {
            var li_1=document.getElementById("li_1");
            var oL_1=document.getElementById("oL_1");
            if (oL_1.style.display=="none"){
                oL_1.style.display="block";
            }else {
                oL_1.style.display="none";
            }

        }
        function on_Click_2() {
            var li_2=document.getElementById("li_2");
            var oL_2=document.getElementById("oL_2");
            if (oL_2.style.display=="none"){
                oL_2.style.display="block";
            }else {
                oL_2.style.display="none";
            }
        }
        function on_Click_3() {
            var li_3=document.getElementById("li_3");
            var oL_3=document.getElementById("oL_3");
            if (oL_3.style.display=="none"){
                oL_3.style.display="block";
            }else {
                oL_3.style.display="none";
            }
        }
        function on_Click_4() {
            var li_4=document.getElementById("li_4");
            var oL_4=document.getElementById("oL_4");
            if (oL_4.style.display=="none"){
                oL_4.style.display="block";
            }else {
                oL_4.style.display="none";
            }
        }
    </script>
</head>
<body >

<ul>
    <li id="li_1" onclick="on_Click_1()">注册&认证
        <ol id="oL_1" style="display: none" >
            <li>注册激活</li>
            <li>安全登录</li>
            <li>支付宝认证</li>
        </ol>
    </li>

    <li id="li_2" onclick="on_Click_2()">买家帮助
        <ol id="oL_2" style="display: none">
            <li>宝贝搜索,浏览</li>
            <li>了解卖家</li>
            <li>出价及付款</li>
        </ol>
    </li>


    <li id="li_3" onclick="on_Click_3()">卖家帮助
        <ol id="oL_3" style="display: none">
            <li>店铺设置管理</li>
            <li>商品发布出售&推荐</li>
            <li>成交后发货&评价</li>
            <li>优惠券和红包</li>
        </ol>
    </li>


    <li id="li_4" onclick="on_Click_4()">个人资料修改
        <ol id="oL_4" style="display: none">
            <li>我的淘宝功能介绍</li>
            <li>修改个人信息</li>
            <li>淘宝/支付宝账户绑定</li>
        </ol>
    </li>
</ul>

</body>
</html>

原文地址:https://www.cnblogs.com/Dionexin/p/5959941.html