1. 获取ip地址
2. 与允许的ip范围 进行比较
代码如下：
$ip = getIP();
function getIP()
{
$onlineip = '';
if(getenv('HTTP_CLIENT_IP') && strcasecmp(getenv('HTTP_CLIENT_IP'), 'unknown'))
{
$onlineip = getenv('HTTP_CLIENT_IP');
} else if (getenv('HTTP_X_FORWARDED_FOR') && strcasecmp(getenv('HTTP_X_FORWARDED_FOR'), 'unknown')) {
$onlineip = getenv('HTTP_X_FORWARDED_FOR');
} else if (getenv('REMOTE_ADDR') && strcasecmp(getenv('REMOTE_ADDR'), 'unknown')) {
$onlineip = getenv('REMOTE_ADDR');
} else if (isset($_SERVER['REMOTE_ADDR']) && $_SERVER['REMOTE_ADDR'] && strcasecmp($_SERVER['REMOTE_ADDR'], 'unknown')) {
$onlineip = $_SERVER['REMOTE_ADDR'];
}
preg_match("/[\d\.]{7,15}/", $onlineip, $onlineipmatches);
$onlineip = empty($onlineipmatches[0]) ? 'unknown' : $onlineipmatches[0];
return $onlineip;
}
