前端面试题：统计每一个标签出现的次数 

<!DOCTYPE html>
<html>
<head>
  <title>题目：统计标签的个数</title>
</head>

<body>
<div>
  <ul>
    <li><br></li>
    <li></li>
  </ul>
  <br>
  <section>
    <p>
      <span></span>
      <b></b>
      <article></article>
    </p>
  </section>
</div>
<script>
  'use strict';

  function foo(){
    var target, o, i = 0, clone;
    if(typeof arguments[0] == 'boolean'){
      o = arguments[1];
      target = arguments[2]
    }else{
      o = {};
      target = arguments[0];
    }

    var children = target.children;
    var len = children.length;

    o[target.nodeName] = 1;

    for(;i<len;i++){
      var child = children[i];
      if(child.children.length){
        foo(true, o, child);
      }else{
        var nodename = child.nodeName;
        o[nodename] = o[nodename] ? o[nodename] + 1 : 1;
      }
    }

    return o;
  }

  console.log(foo(document.querySelector('div')))
</script>
</body>
</html>

 

posted @ 2015-04-01 14:02  Unintended  阅读(920)  评论(0)    收藏  举报