我的结果有错误？？
<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_nextSibling(n){
var x=n.nextSibling;
while (x && x.nodeType!=1){
x=x.nextSibling;
}
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+"<br>");
}else{
document.write("<br>已经是最后一个节点");
}
function get_previousSibling(m)
{
var s = m.previousSibling;
while(s && s.nodeType != 1)
{
s=s.preiousSibling;
}
return s;
}
var s = document.getElementsByTagName("li")[2];
// var s = document.getElementById("b");
document.write(s.nodeName);
document.write(" = ");
document.write(s.innerHTML);
var f = get_previousSibling(s);
if(f != null)
{
document.write("<br/>previousSibling");
document.write(f.nodeName);
document.write(" = ");
document.write(f.innerHTML);
}else
{
document.write("<br>已经是第一个节点！");
}
结果是“已经是第一个节点”
不应该是jquery吗
