请教怎么php怎么返回变量+组装html给ajax

return "$result,$a,$b";<br />

success:function(json){<br />
            a = json.split(',');

function html($select,$name){<br />
global $pagecon;<br />
$a='1';<br />
$b='2';<br />
$result='';<br />
$result.='<ul id="thumbs">';<br />
while($row=$select->fetch()){<br />
$result.='<li class="'.$name.'isotope-item">';<br />
$result.='<img src="ztImg/'.$row['riseimg'].'"width=235 height=300 alt=""//></div><ul>';<br />
$result.='<h3 class="title">'.$row['ztname'].'</h3>';<br />
$result.='<span class="category">'. $row['zttype'].'</span>';    <br />
$result.='<p class="intro">推荐日期:'.$row['zttime'].'</p></div></li>';<br />
    }<br />
$result.='</ul>';<br />
$result.='<center><h4>'.$pagecon.'</h4></center>';<br />
return $result.'--'.$a.'--'.$b;//用--来连接返回<br />
}

function getData(page){<br />
        alert('ok');<br />
     $.ajax({<br />
     type:'post',<br />
     url:'action/test.php',<br />
    data: {'pageNum':page-1},<br />
        beforeSend:function(){<br />
            $("#sss ul").append("<li id='loading'>loading...</li>");<br />
        },<br />
        success:function(json){<br />
            var arr=json.split('--');<br />
            $("#sss ul").empty();<br />
            result = arr['0']//获得来自php的变量$result<br />
            total = arr['0']//获得来自php的变量$a<br />
            pageSize = //获得来自php的变量$b<br />
             $("div#sss").html(data);<br />
        },<br />
        complete:function(){ //生成分页条<br />
            getPageBar();<br />
        },<br />
        error:function(){<br />
            alert("数据加载失败");<br />
        }<br />
    });<br />
}