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Implementation method of javascript drop-down list menu_javascript skills

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May 16, 2016 pm 03:31 PM

I wrote this before "Implementation method of displaying tree menu in javascript drop-down list" The embodiment of the menu, but after writing it, I found that it is not suitable. The height needs to be accurately controlled, and also Not very nice. Now we use table to encapsulate it. We know that after each row of the table is full, the next row will be automatically added. This is much better than before when we set the height ourselves.
1. Both clicks can coexist (as long as the function is written in different ways)
dispaly is also set by myself, operating the child nodes through the parent node, displaying or not;

/* function open1(node){ 
   
   //通过父节点来操作兄弟节点 
    
   当点击之后出现之后，直接就能打开但是要求在点开一个时候，其余的都关掉 
 
    var nodes = node.parentNode; 
    var nn = nodes.getElementsByTagName("ul")[0]; 
    with (nn.style) { 
     display = (display == "block") &#63; "none" : "block"; 
    } 
   }*/ 
   </script>

2. Only one is allowed to be opened after clicking, and the rest must be closed

<script type="text/javascript"> 
    function list1(node){ 
    //这是要对全部操作，必须要得到所有的对象 （根据table 的id 来获得） 
    //根据this判断，不是属于this，那么就关闭 
    //alert("aa"); 
    //1，获得点击对象的值 
    var nodes = node.parentNode;//传入当前的父节点 
    var nn = nodes.getElementsByTagName("ul")[0];//得到当前的对象，要是遍历所有，与这个对象一样，就设置相反的情况，其余的全部关闭 
    //2，获得全部对象 
    var mm = document.getElementById("menuid"); 
    var names = mm.getElementsByTagName("ul"); 
     
    //3，开始一一配对 
    for (var x = 0; x < names.length; x++) { 
     /*这样写，可以简化，利用下面的方法 
      if (names[x] == nn) { 
      if (nn.className == "open2") { 
       nn.className = "close2"; 
      } 
      else { 
       nn.className = "open2"; 
      } 
     }else { 
      nn.className = "close2"; 
     }*/ 
     if(names[x]==nn&&names[x].className!="open2"){ 
       nn.className="open2"; 
     }else{ 
       names[x].className="close2"; 
     } 
    } 
   } 
 </script>

Css style writing:

<style type="text/css"> 
  ul{ 
   list-style:none; 
   margin:0px; 
   padding:0px; 
  } 
  table{ 
   border:#00ff40 solid 1px; 
  } 
  table a{ 
   text-decoration:none; 
  } 
  table tr td ul{ 
   display:none; 
  } 
  .open2{ 
   display:block; 
   background:#8080ff; 
  } 
  .close2{ 
   display:none; 
  }

Rendering (only one can be opened):

Full code:

<!DOCTYPE html> 
<html> 
 <head> 
 <title>qqMenu.html</title> 
 <style type="text/css"> 
  ul{ 
   list-style:none; 
   margin:0px; 
   padding:0px; 
  } 
  table{ 
   border:#00ff40 solid 1px; 
  } 
  table a{ 
   text-decoration:none; 
  } 
  table tr td ul{ 
   display:none; 
  } 
  .open2{ 
   display:block; 
   background:#8080ff; 
  } 
  .close2{ 
   display:none; 
  } 
 </style> 
 <script type="text/javascript"> 
  /* function open1(node){ 
   
   //通过父节点来操作兄弟节点 
    
   当点击之后出现之后，直接就能打开但是要求在点开一个时候，其余的都关掉 
 
    var nodes = node.parentNode; 
    var nn = nodes.getElementsByTagName("ul")[0]; 
    with (nn.style) { 
     display = (display == "block") &#63; "none" : "block"; 
    } 
   }*/ 
   </script> 
   <script type="text/javascript"> 
    function list1(node){ 
    //这是要对全部操作，必须要得到所有的对象 （根据table 的id 来获得） 
    //根据this判断，不是属于this，那么就关闭 
    //alert("aa"); 
    //1，获得点击对象的值 
    var nodes = node.parentNode;//传入当前的父节点 
    var nn = nodes.getElementsByTagName("ul")[0];//得到当前的对象，要是遍历所有，与这个对象一样，就设置相反的情况，其余的全部关闭 
    //2，获得全部对象 
    var mm = document.getElementById("menuid"); 
    var names = mm.getElementsByTagName("ul"); 
     
    //3，开始一一配对 
    for (var x = 0; x < names.length; x++) { 
     /*这样写，可以简化，利用下面的方法 
      if (names[x] == nn) { 
      if (nn.className == "open2") { 
       nn.className = "close2"; 
      } 
      else { 
       nn.className = "open2"; 
      } 
     }else { 
      nn.className = "close2"; 
     }*/ 
     if(names[x]==nn&&names[x].className!="open2"){ 
       nn.className="open2"; 
     }else{ 
       names[x].className="close2"; 
     } 
    } 
   } 
 </script> 
  
 <!--<link rel="stylesheet" type="text/css" href="./styles.css">--> 
 </head> 
 
 <body > 
 <table id="menuid"> 
  <tr> 
   <td> 
    <!--<a href="javascript:void(0)" onclick="open1(this)">同事栏</a>--> 
    <a href="javascript:void(0)" onclick="list1(this)">同事栏</a> 
    <ul > 
     <li>同事1</li> 
     <li>同事2</li> 
     <li>同事3</li> 
     <li>同事4</li> 
    </ul> 
     
   </td> 
  </tr> 
  <tr> 
   <td> 
    <!--<a href="javascript:void(0)" onclick="open1(this)">同学栏</a>--> 
    <a href="javascript:void(0)" onclick="list1(this)">同学栏</a> 
    <ul> 
     <li>同学1</li> 
     <li>同学2</li> 
     <li>同学3</li> 
     <li>同学4</li> 
    </ul> 
   </td> 
  </tr> 
  <tr> 
   <td> 
    <!--<a href="javascript:void(0)" onclick="open1(this)">黑名单栏</a>--> 
    <a href="javascript:void(0)" onclick="list1(this)">黑名单栏</a> 
    <ul> 
     <li>黑名单同学1</li> 
     <li>黑名单同学2</li> 
     <li>黑名单同学3</li> 
     <li>黑名单同学4</li> 
    </ul> 
   </td> 
  </tr> 
  
 </table> 
 </body> 
</html>

I believe you should have a general idea through the introduction of these two articles. Some of the effects of this article are slightly crude, and you can further improve them.

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