获取百度 搜索关键字

获取百度 搜索关键字的关键在于获取访问跳转url  在百度搜索中会自带关键字 word或者wd 通过获得跳转url $_SERVER['HTTP_REFERER'] 来正则匹配出关键字
public function search_word_from($referer) {
//        $referer = isset($_SERVER['HTTP_REFERER'])?$_SERVER['HTTP_REFERER']:'';
        if(strstr( $referer, 'baidu.com')){ //百度
            preg_match( "|baidu.+wo?r?d=([^\\&]*)|is", $referer, $tmp );
            if(isset($tmp[1])){
                $keyword = urldecode( $tmp[1] );
                $from = 'baidu';
            }else{
                $keyword ='';
                $from = '';
            }
        }elseif(strstr( $referer, 'google.com') or strstr( $referer, 'google.cn')){ //谷歌
            preg_match( "|google.+q=([^\\&]*)|is", $referer, $tmp );
            if(isset($tmp[1])){
                $keyword = urldecode( $tmp[1] );
                $from = 'google';
            }else{
                $keyword ='';
                $from = '';
            }

        }elseif(strstr( $referer, 'so.com')){ //360搜索
            preg_match( "|so.+q=([^\\&]*)|is", $referer, $tmp );
            if(isset($tmp[1])){
                $keyword = urldecode( $tmp[1] );
                $from = '360';
            }else{
                $keyword ='';
                $from = '';
            }
        }elseif(strstr( $referer, 'sogou.com')){ //搜狗
            preg_match( "|sogou.com.+query=([^\\&]*)|is", $referer, $tmp );
            if(isset($tmp[1])){
                $keyword = urldecode( $tmp[1] );
                $from = 'sogou';
            }else{
                $keyword ='';
                $from = '';
            }

        }elseif(strstr( $referer, 'soso.com')){ //搜搜
            preg_match( "|soso.com.+w=([^\\&]*)|is", $referer, $tmp );
            if(isset($tmp[1])){
                $keyword = urldecode( $tmp[1] );
                $from = 'soso';
            }else{
                $keyword ='';
                $from = '';
            }
        }else {
            $keyword ='';
            $from = '';
        }

        return array('keyword'=>$keyword,'from'=>$from);
    }