通过PHP判断搜索引擎蜘蛛是否访问你的网站

搜索引擎的蜘蛛访问网站是通过远程抓取页面来进行的，我们不能使用JS代码来取得蜘蛛的Agent信息，但是我们可以通过image标签，这样我们就可以得到蜘蛛的agent资料了，通过对agent资料的分析，就可以确定蜘蛛的种类、性别等因素，我们在通过数据库或者文本来记录就可以进行统计了。
数据库结构：

#
# 表的结构 `naps_stats_bot`
#

Create TABLE `naps_stats_bot` (
`botid` int(10) unsigned NOT NULL auto_increment,
`botname` varchar(100) NOT NULL default ‘’,
`botagent` varchar(200) NOT NULL default ‘’,
`bottag` varchar(100) NOT NULL default ‘’,
`botcount` int(11) NOT NULL default ‘0′,
`botlast` datetime NOT NULL default ‘0000-00-00 00:00:00′,
`botlasturl` varchar(250) NOT NULL default ‘’,
UNIQUE KEY `botid` (`botid`),
KEY `botname` (`botname`)
) TYPE=MyISAM AUTO_INCREMENT=9 ;

#
# 导出表中的数据 `naps_stats_bot`
#

Insert INTO `naps_stats_bot` VALUES (1, ‘Googlebot’, ‘Googlebot/2.X (+http://www.googlebot.com/bot.html)’, ‘googlebot’, 0, ‘0000-00-00 00:00:00′, ‘’);
Insert INTO `naps_stats_bot` VALUES (2, ‘MSNbot’, ‘MSNBOT/0.1 (http://search.msn.com/msnbot.htm)’, ‘msnbot’, 0, ‘0000-00-00 00:00:00′, ‘’);
Insert INTO `naps_stats_bot` VALUES (3, ‘Inktomi Slurp’, ‘Slurp/2.0′, ’slurp’, 0, ‘0000-00-00 00:00:00′, ‘’);
Insert INTO `naps_stats_bot` VALUES (4, ‘Baiduspider’, ‘Baiduspider+(+http://www.baidu.com/search/spider.htm)’, ‘baiduspider’, 0, ‘0000-00-00 00:00:00′, ‘’);
Insert INTO `naps_stats_bot` VALUES (5, ‘Yahoobot’, ‘Mozilla/5.0+(compatible;+Yahoo!+Slurp;+http://help.yahoo.com/help/us/ysearch/slurp)’, ’slurp’, 0, ‘0000-00-00 00:00:00′, ‘’);
Insert INTO `naps_stats_bot` VALUES (6, ‘Sohubot’, ’sohu-search’, ’sohu-search’, 0, ‘0000-00-00 00:00:00′, ‘’);
Insert INTO `naps_stats_bot` VALUES (7, ‘Lycos’, ‘Lycos/x.x’, ‘lycos’, 0, ‘0000-00-00 00:00:00′, ‘’);
Insert INTO `naps_stats_bot` VALUES (8, ‘Robozilla’, ‘Robozilla/1.0′, ‘robozilla’, 0, ‘0000-00-00 00:00:00′, ‘’);

PHP程序：

<?php






error_reporting(E_ALL & ~E_NOTICE);

function get_naps_bot()
{
         $useragent = strtolower($_SERVER['HTTP_USER_AGENT']);

         if (strpos($useragent, 'googlebot') !== false){
                 return 'Googlebot';
         }

         if (strpos($useragent, 'msnbot') !== false){
                 return 'MSNbot';
         }

         if (strpos($useragent, 'slurp') !== false){
                 return 'Yahoobot';
         }

         if (strpos($useragent, 'baiduspider') !== false){
                 return 'Baiduspider';
         }

         if (strpos($useragent, 'sohu-search') !== false){
                 return 'Sohubot';
         }

         if (strpos($useragent, 'lycos') !== false){
                 return 'Lycos';
         }

         if (strpos($useragent, 'robozilla') !== false){
                 return 'Robozilla';
         }
         return false;
}

$tlc_thispage = addslashes($_SERVER['HTTP_USER_AGENT']);
//添加蜘蛛的抓取记录
$searchbot = get_naps_bot();
if ($searchbot) {
         $DB_naps->query("Update naps_stats_bot SET botcount=botcount+1, botlast=NOW(), botlasturl='$tlc_thispage' Where botname='$searchbot'");
}

?>