下面是实现的代码: /** * PHP+MySQL * CREATE TABLE IF NOT EXISTS `ip_poll` ( * `ip` varchar(15) NOT NULL, * `date` datetime NOT NULL * ) ENGINE=MyISAM DEFAULT CHARSET=latin1; * */ function getIP() { $ip=”"; if (getenv(“HTTP_CLIENT_IP”)) $ip = getenv(“HTTP_CLIENT_IP”); else if(getenv(“HTTP_X_FORWARDED_FOR”)) $ip = getenv(“HTTP_X_FORWARDED_FOR”); else if(getenv(“REMOTE_ADDR”)) $ip = getenv(“REMOTE_ADDR”); else $ip = “”; return $ip; } function checkVote() { $ip= getIP(); $sql= “select count(*) from ip_poll where ip = ‘”.$ip.”‘ and SUBSTR(date,1,10) = ‘”.date(“Y-m-d”).”‘”; if($res= mysql_query($sql)) { $row= mysql_num_rows($res); if($row == 0) { $sqlIns= “insert into ip_poll values (‘”.$ip.”‘,now());”; if(mysql_query($sqlIns)) return true; else return false; }else{ return false; } }else{ return false; } } ?>