php的一些变量

访问地址： $_SERVER['HTTP_REFERER']
访问ip：
if (@$_SERVER['HTTP_X_FORWARDED_FOR']) {
$ip = @$_SERVER['HTTP_X_FORWARDED_FOR'];
} elseif (@$_SERVER["HTTP_CLIENT_IP"]) {
$ip = @$_SERVER["HTTP_CLIENT_IP"];
} elseif (@$_SERVER["REMOTE_ADDR"]) {
$ip = @$_SERVER["REMOTE_ADDR"];
} elseif (getenv("HTTP_X_FORWARDED_FOR")) {
$ip = getenv("HTTP_X_FORWARDED_FOR");
} elseif (getenv("HTTP_CLIENT_IP")) {
$ip = getenv("HTTP_CLIENT_IP");
} elseif (getenv("REMOTE_ADDR")) {
$ip = getenv("REMOTE_ADDR");
} else {
$ip = "Unknown";
}