PHP + Ajax 简单的投票系统实例（实时显示结果部分）

function ajaxSend(url,changeObjId, formAction)
{
    var objId = changeObjId;
    var xmlHttp = false;
    if(window.ActiveXObject)
    {
        xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
    }
    else if(window.XMLHttpRequest)
    {
        xmlHttp = new XMLHttpRequest();
    }

    if (xmlHttp)
    {
        xmlHttp.open(formAction, url, true);
        if(!changeObjId=="")
        {
            xmlHttp.onreadystatechange = function()
            {
                if (xmlHttp.readyState == 4 && xmlHttp.status == 200)
                {
                    document.getElementById(changeObjId).innerHTML = xmlHttp.responseText;
                    delete xmlHttp;
                    xmlHttp = null;
                }
            }
        }
        xmlHttp.send(null);    
    }
}

<script src="js/ajax.js"></script>
<script>
function showVotes($code){
    ajaxSend("ajaxnum.php?code="+$code,$code,"POST");
}
</script>

<?    for($j=0;$j<countDetailIds(getSeriesById($i,'series')->id);$j++)   
    {   
        $seriesDetail=getDetailBySeriesId(getSeriesById($i,'series')->id);
        $tohtml = "htmls/".$i.($j+1).".html";
        $code = "P".$i.'-'.($j+1);
        $img=$seriesDetail[$j]->bgimg;
        $imgsize = getimagesize($seriesDetail[$j]->bgimg);
        $simg = $seriesDetail[$j]->img;
        if($imgsize[0]>=$imgsize[1])
        {
            $toW=200;
            $toH=139;
        }
        else
        {
            $toW=$imgsize[0]*139/$imgsize[1];
            $toH=139;
        }
        if(!file_exists($simg)){
            if(!$imageTreat->ImageResize($img, $toW, $toH,$simg))
                print_r($img."===>".$toW.'*'.$toH."   To   ".$simg."==========> Failed ");
        }       
?>
   
  <div style="float:left;width:230px;text-align:center;">
    <table><tr><td class=boximg width="200"><a href="showimg.php?id=<?=$seriesDetail[$j]->id?>&sid=<?=$j?>"><img src="<?=$seriesDetail[$j]->img?>"></a></td>
        </tr>
        <tr><td class=boxtxt>P<?=$i?>　<?=$j+1?>－<?=$seriesDetail[$j]->name?></td></tr>
        <tr><td>目前有人<span id="<?=$code?>"></span>投票！</td></tr>
        </table>
      </div>
<?    }    ?>

<?
    require_once('conn.inc.php');
    $sql = "select code from `voteMgr` where code = ".'"'.trim($_REQUEST['code']).'"';
    $res=mysql_query($sql) or die(mysql_error());
    echo mysql_num_rows($res);            //要打印出来的，不要return
?>