jquery解析json使用$.each()

$.post('action.do',null,function(message){
var data=eval("("+message+")");
var html='<div class="title"><div class="text">text</div></div><ul class="content">';
$.each(data.esop,function(index,item){
if(index==0){
html+='<li class="first">'+item.kpi_name+'：<span class="num">'+item.kpi_value+'</span></li>';
}else if(index==(data.esop.length-1)){
html+='<li class="last">'+item.kpi_name+'：<span class="num">'+item.kpi_value+'</span></li>';
}else{
html+='<li>'+item.kpi_name+'：<span class="num">'+item.kpi_value+'</span></li>';
}
});
html+='<div class="bottom"></div></ul>';
$("#tab").html(html);
},'post');