节点值nodeValue

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    <title>节点值nodeValue</title>
    <!-- 
        node.nodeValue;获取node节点的值
     -->
</head>
<body>
    <span>我是节点里面的值</span>
    <script>
        var span=document.getElementsByTagName("span")[0];
        var a=span.firstChild;//获取span节点内的第一个子节点
        console.log(a.nodeValue);//获取a节点的值
    </script>
</body>
</html>