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                        /JavaScript進(jìn)階篇

var y=get_nextSibling(x); ? 本節(jié)課貌似不需要寫代碼，已經(jīng)寫好了？

我把這段代碼復(fù)制到瀏覽器里去，結(jié)果不一樣

<!DOCTYPE?HTML>
<html>
<head>
<meta?http-equiv="Content-Type"?content="text/html;?charset=utf-8">
<title>nextSibling</title>
</head>
<body>
<ul?id="u1">???
????????????<li?id="a">javascript</li>???
????????????<li?id="b">jquery</li>???
????????????<li?id="c">html</li>???
????????</ul>???
????????<ul?id="u2">???
????????????<li?id="d">css3</li>???
????????????<li?id="e">php</li>???
????????????<li?id="f">java</li>???
????????</ul>???
<script?type="text/javascript">
????function?get_previousSibling(n){
????????var?x=n.previousSibling;
????????while?(x?&&?x.nodeType!=1){
????????????x=x.previousSibling;
????????}
????????return?x;
????}

????var?x=document.getElementsByTagName("li")[0];
????document.write(x.nodeName);
????document.write("?=?");
????document.write(x.innerHTML);
????
????var?y=get_nextSibling(x);
????
????if(y!=null){
????????document.write("<br?/>nextsibling:?");
????????document.write(y.nodeName);
????????document.write("?=?");
????????document.write(y.innerHTML);
????}else{
??????document.write("<br>已經(jīng)是最后一個節(jié)點");??????
????}

</script>
</body>
</html>


瀏覽器顯示：
javascript
jquery
html
css3
php
java
LI?=?javascript??

沒有教程中的最后那一行，而且這里的var?y=get_nextSibling(x);這段代碼，明顯是單純的賦值不是函數(shù)吧？沒辦法把x的值傳給y吧？