获取ip地址

$type       =  $type ? 1 : 0;
static $ip  =   NULL;
if ($ip !== NULL) return $ip[$type];
if (isset($_SERVER['HTTP_X_FORWARDED_FOR'])) {
    $arr    =   explode(',', $_SERVER['HTTP_X_FORWARDED_FOR']);
    $pos    =   array_search('unknown',$arr);
    if(false !== $pos) unset($arr[$pos]);
    $ip     =   trim($arr[0]);
}elseif (isset($_SERVER['HTTP_CLIENT_IP'])) {
    $ip     =   $_SERVER['HTTP_CLIENT_IP'];
}elseif (isset($_SERVER['REMOTE_ADDR'])) {
    $ip     =   $_SERVER['REMOTE_ADDR'];
}
// IP地址合法验证
$long = sprintf("%u",ip2long($ip));
$ip   = $long ? array($ip, $long) : array('0.0.0.0', 0);
return $ip[$type];