ajax取消挂起请求的处理方法

<style><!--*{margin:0;padding:0;}li{list-style-type:none;}.tab{width:240px;margin: 50px auto;}.nav ul{clear:both;}.nav ul li{margin-right: 4px;padding: 1px 6px;border:1px solid #ccc;width:60px;background: #f1f1f1;float: left;text-align: center;cursor: pointer;}.nav ul li.selected{color:#fff;background:blue;}

#box{width:238px;border: 1px solid #ccc;height: 100px;clear: both;overflow: hidden;}.addBg{background: url('./img/loading.gif') no-repeat center;}--></style><script type="text/javascript" src="//www.jb51.net/itoks/admin/js/jquery-1.4.4.min.js"></script><script type="text/javascript">// <![CDATA[$(function(){var ajax;$.ajax({type: 'GET',url: '4.php',data: 'what=1',success:function(data){//加载成功后移除小图标// $("#box").removeClass("addBg");// $('#box').html(data);$("#box").removeClass("addBg").html(data);

},beforeSend:function() //{//加载过程中得等待小图标,先清空box的内容$("#box").html('').addClass("addBg");}});

$('.nav ul li').click(function(){

$(this).addClass('selected').siblings().removeClass('selected');var liName = $(this).attr('name');//alert(liName);//加载过程中得等待小图标,先清空box的内容$("#box").html('').addClass("addBg");

if(ajax){ajax.abort();//alert(ajax);}

ajax = $.get('4.php',{what : liName},function(data){//加载成功后移除小图标$("#box").removeClass("addBg");$('#box').html(data);});

});});// ]]></script><div class="tab"><div class="nav"><ul><li class="selected">tab 1</li><li>tab 2</li><li>tab 3</li></ul></div><div id="box"> </div></div>