求助大神！为什么要二次点按钮length才显示=0，第一次点按钮清空了内容而length仍为11
<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>无标题文档</title>
</head>
<body>
<div id="content">
<h1>html</h1>
<h1>php</h1>
<h1>javascript</h1>
<h1>jquery</h1>
<h1>java</h1>
</div>
<p id="re"></p>
<script type="text/javascript">
function clearText() {
var content=document.getElementById("content");
var len=content.childNodes.length;
for(i=0;i<len;i++){
content.removeChild(content.childNodes[0]);
}
document.getElementById("re").innerHTML=len;
}
</script>
<button onclick="clearText()">清除节点内容</button>
</body>
</html>
