只有输入控件,如text,radio等才能使用document.getElementsByName返回<ul><li name="aa">aa</li><li name="aa">aa</li></ul>
<input type="text" name="bb" /><input type="text" name="bb" />
<script>
alert(document.getElementsByName("aa").length)
alert(document.getElementsByName("bb").length)
</script>

解决方案 »

  1.   

    我测试了下,把你的name 换成id就正常了!
      

  2.   

    <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
    <HTML>
     <HEAD>
      <TITLE> New Document </TITLE>
      <META NAME="Generator" CONTENT="EditPlus">
      <META NAME="Author" CONTENT="">
      <META NAME="Keywords" CONTENT="">
      <META NAME="Description" CONTENT="">
     </HEAD> <BODY>
      
    <ul class="search_cat">
        <p>
            按<b>系列</b>选择:</p><span onclick="ShowHideSeries(this)">显示所有</span>        
                <li style='display:'><a href='/List.htm?SeriesCode=0557'>明星系列</a> <span class="cat_num">(2)</span> </li>        
                <li style='display:'><a href='/List.htm?SeriesCode=0558'>小卡漫系列</a> <span class="cat_num">(1)</span> </li>        
                <li style='display:'><a href='/List.htm?SeriesCode=0568'>雅汀系列</a> <span class="cat_num">(1)</span> </li>        
                <li style='display:'><a href='/List.htm?SeriesCode=0593'>玛莉珍系列</a> <span class="cat_num">(1)</span> </li>        
                <li style='display:'><a href='/List.htm?SeriesCode=0613'>美琳蒂系列</a> <span class="cat_num">(1)</span> </li>        
                <li name='liSeries' style='display:none'><a href='/List.htm?SeriesCode=0656'>普玛系列</a> <span class="cat_num">(4)</span> </li>        
                <li id='liSeries' style='display:none'><a href='/List.htm?SeriesCode=0683'>艾适佳系列</a> <span class="cat_num">(2)</span> </li>        
                <li id='liSeries' style='display:none'><a href='/List.htm?SeriesCode=0688'>手机套系列</a> <span class="cat_num">(1)</span> </li>        
                <li id='liSeries' style='display:none'><a href='/List.htm?SeriesCode=0689'>腕带系列</a> <span class="cat_num">(3)</span> </li>        
                <li id='liSeries' style='display:none'><a href='/List.htm?SeriesCode=0719'>奥黛丽系列</a> <span class="cat_num">(5)</span> </li>       
    </ul>
    <script>function ShowHideSeries(obj)
    {
        alert(obj);
        if(obj.innerHTML=="显示所有")
        {
            alert("1");
            obj.innerHTML=="精简显示"
            objLi = document.getElementsByName("liSeries");
            alert(objLi.length);//为什么这里取不到我的li呢 谢谢
            for(var i=0;i<=objLi.length-1;i++)
            {
                objLi[i].style.display="";
            }
        }    
        else
        {
            alert("2");
            obj.innerHTML=="显示所有"
            objLi = document.getElementsByName("liSeries");
            for(var i=0;i<=objLi.length-1;i++)
            {
                objLi[i].style.display="none";
            }
        }
        
    }
    </script>
     </BODY>
    </HTML>
      

  3.   

    RE:我测试了下,把你的name 换成id就正常了!
    ---------------------------
    还真的哦
    那奇怪了,这里他没有Name为什么byName会有用呢
      

  4.   

    可以用classname
    <ul class="search_cat">
        <p>
            按<b>系列</b>选择:</p><span onclick="ShowHideSeries(this)">显示所有</span>        
                <li style='display:'><a href='/List.htm?SeriesCode=0557'>明星系列</a> <span class="cat_num">(2)</span> </li>        
                <li style='display:'><a href='/List.htm?SeriesCode=0558'>小卡漫系列</a> <span class="cat_num">(1)</span> </li>        
                <li style='display:'><a href='/List.htm?SeriesCode=0568'>雅汀系列</a> <span class="cat_num">(1)</span> </li>        
                <li style='display:'><a href='/List.htm?SeriesCode=0593'>玛莉珍系列</a> <span class="cat_num">(1)</span> </li>        
                <li style='display:'><a href='/List.htm?SeriesCode=0613'>美琳蒂系列</a> <span class="cat_num">(1)</span> </li>        
                <li class='liSeries' style='display:none'><a href='/List.htm?SeriesCode=0656'>普玛系列</a> <span class="cat_num">(4)</span> </li>        
                <li class='liSeries' style='display:none'><a href='/List.htm?SeriesCode=0683'>艾适佳系列</a> <span class="cat_num">(2)</span> </li>        
                <li class='liSeries' style='display:none'><a href='/List.htm?SeriesCode=0688'>手机套系列</a> <span class="cat_num">(1)</span> </li>        
                <li class='liSeries' style='display:none'><a href='/List.htm?SeriesCode=0689'>腕带系列</a> <span class="cat_num">(3)</span> </li>        
                <li class='liSeries' style='display:none'><a href='/List.htm?SeriesCode=0719'>奥黛丽系列</a> <span class="cat_num">(5)</span> </li>       
    </ul>
    <script>
    var lis = document.getElementsByTagName('li'), myLis = [];
    for(var i=0; i<lis.length; i++)
    if(lis[i].className == 'liSeries') myLis.push(lis[i]);
    alert(myLis.length);
    </script>
      

  5.   

    ID在页面里是唯一的, 这样会有问题吧!
    上面的用classname的可以写成一个方法, Prototype框架里有个方法
    getElementsByClassName