求索阁

    如果你是第一次来到本站，又是第一次阅览文章，只要你刷新一下页面，就可以在右边栏见到效果了。这也许是真正意义上的足迹吧，看过文章就给记录，不管你是潜水也好，水车也好。实现原理是给客户端浏览器加个cookie，每访问一次记录一次，服务器表示无压力。。。
    实现步骤一：把以下代码加入WordPress主题内的function.php中----

<?php
function save_posts_viewed($maxCount=10){
    global $post;
    $done=false;
    //新列
    $newList=array();
    $postsViewed="";
    if(isset($_COOKIE['postsViewed'])){
     $postsViewed=$_COOKIE['postsViewed'];
    }
    if(isset($_COOKIE['postsViewed'])&&$postsViewed!=array()){
        $repeat=null;
        $repeated=false;
        foreach ($postsViewed as $k=>$p){
            if($p['ID']==$post->ID){
                $repeat=$p;
                $repeated=true;
            }
            else
            $newList[]=$p;
        }
        if($repeated)
        $newList[]=$repeat;
        else
        $newList[]=array(
            'ID'=>$post->ID,
            'post_title'=>$post->post_title,
            'post_date'=>$post->post_date,
            'viewed_date'=>time()
        );
    }else{
        $newList[]=array(
            'ID'=>$post->ID,
            'post_title'=>$post->post_title,
            'post_date'=>$post->post_date,
            'viewed_date'=>time()
        );
    }
    if(count($newList)>$maxCount){
        $newList2=array();
        $m=1;
        foreach ($newList as $n){
            if($m>count($newList)-$maxCount)
            $newList2[]=$n;
            $m++;
        }
        $newList=$newList2;
    }
    creatCookiesList($newList);
}
function creatCookiesList($newList){
    //setcookie("postsViewed",'', COOKIEPATH, COOKIE_DOMAIN);
    foreach ($newList as $k=>$n){
        setcookie("postsViewed[$k][ID]",$n['ID'],time()+3600*24*365,COOKIEPATH, COOKIE_DOMAIN);
        setcookie("postsViewed[$k][post_title]",$n['post_title'],time()+3600*24*365, COOKIEPATH, COOKIE_DOMAIN);
        setcookie("postsViewed[$k][post_date]",$n['post_date'],time()+3600*24*365, COOKIEPATH, COOKIE_DOMAIN);
        setcookie("postsViewed[$k][viewed_date]",$n['viewed_date'],time()+3600*24*365, COOKIEPATH, COOKIE_DOMAIN);
    }
}
function get_posts_viewed(){
    if(isset($_COOKIE['postsViewed'])){                  
                    $list=$_COOKIE['postsViewed'];
                    $num=0;
                    for ($i=count($list)-1;$i>=0;$i--){
                        $num++;
                    ?>
                        <li style="height:16px;"><span style="margin-right:5px;"><?php echo $num;?>?</span><a href="<?php echo get_permalink($list[$i]['ID'])?>" title="您在 <?php echo date('Y-m-d h:i',$list[$i]['viewed_date'])?>观看了这篇文章"><?php echo $str=$list[$i]['post_title']?></a></li>
                        <?php }
        }else {?>
            <li>你没有浏览过任何文章或者你没有开启cookies。</li>
           <?php }
        }

实现步骤二：
1、先在single.php主循环里面加上（比如get_header();这个函数后面）：

<?php save_posts_viewed(10);?>数字10是记录数量，你可以自己更改。
2、然后在页面任意适合的地方（我放在sidebar.php）里面输出：

<?php get_posts_viewed();?>
   
有关css怎么写，每个人的主题不一样，就不好提供了。

几点说明：

1、如果你不要文章标题前的序列号，可以删除代码：

<span style="margin-right:5px;"><?php echo $num;?>?</span>
2、如果你是国外主机（服务器时间与北京时间不同），建议删除代码：

title="您在 <?php echo date('Y-m-d h:i',$list[$i]['viewed_date'])?>观看了这篇文章"

参考文献