请问个有关问题：怎么获取span内容并存到数组里

请教个问题：如何获取span内容并存到数组里
                        <div id="sample_2" class="sampleDiv">
                             <ul id="leftList">
           <li class="simpleItem">
                <span class="idCol">2&nbsp;&nbsp;</span>
                <span class="nameCol">United States</span>
            </li>
            <li class="simpleItem">
                <span class="idCol">3&nbsp;&nbsp;</span>
                <span class="nameCol">Britain</span>
            </li>
            <li class="simpleItem">
                <span class="idCol">4&nbsp;&nbsp;</span>
                <span class="nameCol">Germany</span>
            </li>
        </ul>
    </div> 
请教个问题，获取ul下li的值问题，我使用下面的代码获取到li值了，但包含着span呢，调试输出li内容时输出结果为：
<span class="idCol">4&nbsp;&nbsp;</span> <span class="nameCol">Germany</span>
其实我想获取到span里的内容，再去掉&nbsp;后存到数组，也就是取出4、Germany存到数组。目前只会这些了，后面的不会了，请教下，这该怎么实现啊？

 var ulNode = document.getElementById("rightList");
  var childrens = ulNode.childNodes;
  var len = childrens.length;
  for(var i=0;i<len;i++)
  {
      //alert(childrens[i].nodeName);
      //alert(childrens[i].innerHTML); //这两条语句是调试用的，想把span内容存到数组里，随表单提交，该怎么实现啊  
  }
------解决方案--------------------

<div id="sample_2" class="sampleDiv">

<ul id="leftList">

           <li class="simpleItem">

                <span class="idCol">2&nbsp;&nbsp;</span>

                <span class="nameCol">United States</span>

            </li>

            <li class="simpleItem">

                <span class="idCol">3&nbsp;&nbsp;</span>

                <span class="nameCol">Britain</span>

            </li>

            <li class="simpleItem">

                <span class="idCol">4&nbsp;&nbsp;</span>

                <span class="nameCol">Germany</span>

            </li>

        </ul>

    </div> 

    <script>

        var lis = document.getElementById('leftList').getElementsByTagName('li');

        var rst = [];

        for (var i = 0; i < lis.length; i++) {

            rst.push(lis[i].innerHTML.replace(/<[^>]+>
------解决方案--------------------
&nbsp;
------解决方案--------------------
\s/gi, ''));//用正则去掉html标签和&nbsp;及空白内容

        }

        alert(rst.join('\n'))

    </script>