节点的值为什么是null

源自：9-7 节点属性

<!DOCTYPE HTML>

<html>

<head>

</head>

<body>

<ul>

<li>javascript</li>

<li>jQuery</li>

</ul>

var aa=document.getElementsByTagName("li");

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

var bb=aa[i].nodeName;

var cc=aa[i].nodeValue;

var dd=aa[i].nodeType;

document.write("第"+(i+1)+"个节点名称:"+bb);

document.write("<br>");

document.write("第"+(i+1)+"个节点的值:"+cc);

document.write("<br>");

document.write("第"+(i+1)+"个节点类型:"+dd);

document.write("<br>");

}

</script>

</body>

</html>

提问者：許_你一世相伴 2018-08-03 14:37