粗略计算在线时间,bug:ip相同

<?PHP
/*

CREATE TABLE db_online (
ip char(20) default NULL,
time char(20) NOT NULL default '',
name char(200) NOT NULL default '游客'
) TYPE=MyISAM

*/

//粗略计算在线时间,bug:ip相同（局域网->外部网）者，只记录一人。不过几率很少

session_start();
//超时时间
$out_time=300;//60*5

$uesr_name=$_SESSION['uesr_name'];

$now=time();
$online="db_online";
$ip=$_SERVER["REMOTE_ADDR"];

mysql_connect("localhost","root","");
mysql_select_db("数据库");
//删除过时用户.
mysql_query("delete from $online where ($now-time)>$out_time or name='$uesr_name' or ip='$ip' ");

if($uesr_name){
mysql_query(" INSERT INTO $online (ip, time, name) VALUES ('$ip','$now','$uesr_name') ");
}else{
mysql_query(" INSERT INTO $online (ip, time, name) VALUES ('$ip','$now','游客') ");
}

?>