Question

我想从没有类名的span元素中提取文本。怎么做到呢？可以搜索具有特定类名的元素，但是如何只获取没有类名的元素？

<span>0m2abBrL+RIHOEA+dZS+OqV3St+nJ/</span>
<wbr></wbr>
<span class="word_break"></span>
<span>zwq73Gfz8MQGB0yS++lfufSOV133huE</span>
<wbr></wbr>
<span class="word_break"></span>
vCB0s5D9w
<span class="text_exposed_hide">...</span>

Answer 1

通过它们迭代并检查我想的类名。

var spans = document.getElementsByTagName('span');
for (var i = 0; i < spans.length; i++) {
    if (spans[i].className == '') {
        //span doesn't have a class
    }
}

Answer 2

可以进行更多优化..但这就是你如何做到这一点..

 function getElementsByNoClassName() {
            var node = document.getElementsByTagName("body")[0];
            var a = [];
            var els = node.getElementsByTagName("*");
            for (var i = 0, j = els.length; i < j; i++)
                if (els[i].className=='') a.push(els[i]);
            return a;
        }

Answer 3

尽管我发现它有多烦人，但我会给出一个jQuery答案（因为mrtsherman用一个真正的答案打败了我）：

$('span:not([class])')

Answer 4

使用Element.querySelectorAll，您可以使用以下代码来实现此目的。

document.getElementsByTagName('span').querySelectorAll('span:not([class])');

Answer 5

在我的朋友投票后，我在核心java脚本中添加了代码：

<html>
<head>
<style>
span{display:block;}
</style>
<script type="text/javascript">
function getElementsByNoClassName() {
            var node = document.getElementsByTagName("span");
            console.log(node.length);
            var a = [];         
            for (var i = 0, j = node.length; i < j; i++){
                   if (node[i].className=='') 
                    node[i].setAttribute("style","color:red;");            
                  }
 }

window.onload=getElementsByNoClassName;
</script>
</head>
<body>
Content with No class is colored in red.
<span>0m2abBrL+RIHOEA+dZS+OqV3St+nJ/</span>
<wbr></wbr>
<span class="word_break"></span>
<span>zwq73Gfz8MQGB0yS++lfufSOV133huE</span>
<wbr></wbr>
<span class="word_break"></span>
vCB0s5D9w
<span class="text_exposed_hide">...</span>
</body>
</html>

这也可以通过jQuery来完成：

<html>
<head>
<style>
span{display:block;}
</style>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.6.1/jquery.min.js" type="text/javascript"></script>
<script type="text/javascript">
$(document).ready(function(){

$("span").filter(
      function(){
         return $(this).attr('class')==undefined
       }).css('color','red');
});
</script>
</head>
<body>
Content with No class is colored in red.
<span>0m2abBrL+RIHOEA+dZS+OqV3St+nJ/</span>
<wbr></wbr>
<span class="word_break"></span>
<span>zwq73Gfz8MQGB0yS++lfufSOV133huE</span>
<wbr></wbr>
<span class="word_break"></span>
vCB0s5D9w
<span class="text_exposed_hide">...</span>
</body>
</html>

如何在javascript中获取没有类名的元素

5 个答案: