PHP禁止个别IP访问网站

想不让某个IP访问网站，可以封他的IP，下面就提供这个方法。看下面的代码。
代码如下:
function get_ip_data(){  
    $ip=file_get_contents("http://ip.taobao.com/service/getIpInfo.php?ip=".get_client_ip());
    $ip = json_decode($ip);
    if($ip->code){
        return false;
    }
    $data = (array) $ip->data;
    if($data['region']=='湖北省' && !isCrawler()){
        exit('http://www.a.net');
    }
}

function isCrawler() {
        $spiderSite= array(
                        "TencentTraveler",
                        "Baiduspider+",
                        "BaiduGame",
                        "Googlebot",
                        "msnbot",
                        "Sosospider+",
                        "Sogou web spider",
                        "ia_archiver",
                        "Yahoo! Slurp",
                        "YoudaoBot",
                        "Yahoo Slurp",
                        "MSNBot",
                        "Java (Often spam bot)",
                        "BaiDuSpider",
                        "Voila",