????function?get_nextSibling(n)
????{
????????var?x=n.nextSibling;
????????while(x.nodeType!=1)
????????{
????????????x=x.nextSibling;
????????}
????????return?x;
????}
????function?get_previousSibling(n)
????{
????????var?x=n.previousSibling;
????????while(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(gè)節(jié)點(diǎn)");??????
????}
????var?z=get_previousSibling(x);
????
????if(z!=null)
????{
????????document.write(z.nodeName);
????????document.write("?=?");
????????document.write(z.innerHTML);
????}