PHP通过访客来路获取搜索关键词的方法

<?phpclass keyword{public function getKeyword($referer){if(strpos($referer,"http://www.baidu.com")> -1 ){$keyword = $this->getbaidukeyword($referer);}else if(strpos($referer,"http://www.google.com")> -1 ){$keyword = $this->getgooglekeyword($referer);}else if(strpos($referer,"http://www.soso.com")> -1 ){$keyword = $this->getsosokeyword($referer);}else if(strpos($referer,"http://www.sogou.com")> -1 ){$keyword = $this->getsogoukeyword($referer);}return $keyword;}//由来路取得百度关键词private function getbaidukeyword($str){$s = strpos($str,'wd=');if($s>-1){$str = substr($str,$s+3);$e = strpos($str,'&');if($e>-1){$str = substr($str,0,$e);}$str = rawurldecode($str);}return $str;}//获得谷歌关键词private function getgooglekeyword($str){$s = strpos($str,'&q=');if($s>-1){$str = substr($str,$s+3);$e = strpos($str,'&');if($e>-1){$str = substr($str,0,$e);}$str = rawurldecode($str);}return $str;}//获得SOSO关键词private function getsosokeyword($str){$s = strpos($str,'?w=');if($s>-1){$str = substr($str,$s+3);$e = strpos($str,'&');if($e>-1){$str = substr($str,0,$e);}$str = rawurldecode($str);}else{$s = strpos($str,'&w=');if($s>-1){$str = substr($str,$s+3);$e = strpos($str,'&');if($e>-1){$str = substr($str,0,$e);}$str = rawurldecode($str);}}return $str;}//获得sogou关键词private function getsogoukeyword($str){$s = strpos($str,'query=');if($s>-1){$str = substr($str,$s+6);$e = strpos($str,'&');if($e>-1){$str = substr($str,0,$e);}$str = rawurldecode($str);}return $str;}}?>