折叠(树形导航栏)

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8"/>
  <title>4_竖向折叠导航菜单_1</title>
  <style type="text/css">
    /*全局设定*/
    .nav{position: absolute;top:100px;left: 100px;}
    *{margin: 0;padding: 0;font-size: 14px;font-size: "微软雅黑";}
    ul{list-style: none;}
    .nav a{text-decoration: none;display: block;width: 135px;height: 30px;line-height: 30px;color: #fff;text-align: center;}    
    /*一级列表设定*/
    .a1{font-size: 16px;height: 35px;line-height: 35px;}
    .nav{background-color: #888;}
    .li0{border-top: 2px solid #bbb;}
    .li0:first-child{border: 0;}
    /*二级列表设定*/
    .nav1{display: none;background-color: #bbb;}
    /*伪类*/
    .li0:hover .a1{background-color: #444;font-weight: bold;font-size: 17px;}
    .nav1 a:hover{background-color: #f60;font-weight: bold;font-size: 15px;}
  </style>
</head>
<body>
  <ul class="nav">
    <li class="li0"><a class="a1" href="javascript:myclick1()">草帽海贼团</a>
      <ul class="nav1" id="nav101">
        <li class="li1"><a href="">路飞</a></li>
        <li class="li1"><a href="">索隆</a></li>
        <li class="li1"><a href="">山治</a></li>
      </ul>
    </li>
    <li class="li0"><a class="a1" href="javascript:myclick2()">海军</a>
      <ul class="nav1" id="nav102">
        <li class="li1"><a href="">黄猿</a></li>
        <li class="li1"><a href="">青雉</a></li>
        <li class="li1"><a href="">赤犬</a></li>
      </ul>
    </li>
    <li class="li0"><a class="a1" href="javascript:myclick3()">现任王下七武海</a>
      <ul class="nav1" id="nav103">
        <li class="li1"><a href="">汉库克</a></li>
        <li class="li1"><a href="">米霍克</a></li>
        <li class="li1"><a href=""></a></li>
        <li class="li1"><a href="">巴基</a></li>
        <li class="li1"><a href="">白胡子二世</a></li>

      </ul>
    </li>
    <li class="li0"><a class="a1" href="javascript:myclick4()">革命军</a>
      <ul class="nav1" id="nav104">
        <li class="li1"><a href=""></a></li>
        <li class="li1"><a href="">萨博</a></li>
        <li class="li1"><a href="">人妖王</a></li>
      </ul>
    </li>
    <li class="li0"><a class="a1" href="javascript:myclick5()">现任四皇</a>
      <ul class="nav1" id="nav105">
        <li class="li1"><a href="">香克斯</a></li>
        <li class="li1"><a href="">凯多</a></li>
        <li class="li1"><a href="">玲玲</a></li>
        <li class="li1"><a href="">蒂奇</a></li>

      </ul>
    </li>
  </ul>
  <script>
    var arr2 =document.getElementsByClassName('nav1');
    function allNone(){
      //事件开始的时候的状态
      for(var i = 0 ; i < arr2.length;i++){
        arr2[i].style.display = 'none';
      }
    }
    //单机第一个
    function myclick1(){
      var x = document.getElementById('nav101');
      if(x.style.display=='block'){
        x.style.display = "none";
      }else{
        allNone();
        x.style.display ='block';
      }
    };
    function myclick2(){
      var x = document.getElementById('nav102');
      if(x.style.display=="block"){
        x.style.display = "none";
      }else{
        allNone();
        x.style.display = 'block';
      }
    }
  </script>
  
</body>
</html>
原文地址:https://www.cnblogs.com/TTTK/p/6297870.html