原生Js获取某个节点后面的第一个标签

window.onload=function(){
var pagecount={$page_count};
document.getElementById('firsts').setAttribute('class','disabled');
document.getElementById('before').setAttribute('class','disabled');
var current=document.getElementById('before').nextSibling;
while(current.nodeType != 1){　　　　　　根据nodeType判断节点属性
current=current.nextSibling;
}
current.setAttribute('class','current');
if(pagecount==1){
document.getElementById('next').setAttribute('class','disabled');
document.getElementById('last').setAttribute('class','disabled');
}
}