jQuery next判定最后一个元素
if($el.next().length === 0){ //结束的代码}
for eg:
<!DOCTYPE html>
<html>
<head>
<script type="text/javascript" src="/jquery/jquery.js"></script>
</head>
<body>
<ul>
<li>list item 1</li>
<li>list item 2</li>
<li >list item 3</li>
<li>list item 4</li>
<li class="third-item">list item 5</li>
</ul>
<script>
$('li.third-item').next().css('background-color', 'red');
var itemlen = $(".third-item").next().length;
if(itemlen == 0){
alert("结束")
}
</script>
</body>
</html>
