php how to check user ip

// Get the user ip way 1

$ip = $_SERVER["REMOTE_ADDR"];

echo $ip;

// Get the user ip way 2

$user_IP = ($_SERVER["HTTP_VIA"]) ? $_SERVER["HTTP_X_FORWARDED_FOR"] : $_SERVER["REMOTE_ADDR"];

$user_IP = ($user_IP) ? $user_IP : $_SERVER["REMOTE_ADDR"];

echo $user_IP;

// Get the user ip way 3

function getRealIp()

{

$ip=false;

if(!empty($_SERVER["HTTP_CLIENT_IP"])){

$ip = $_SERVER["HTTP_CLIENT_IP"];

}

if (!empty($_SERVER['HTTP_X_FORWARDED_FOR'])) {

$ips = explode (", ", $_SERVER['HTTP_X_FORWARDED_FOR']);

if ($ip) { array_unshift($ips, $ip); $ip = FALSE; }

for ($i = 0; $i < count($ips); $i++) {

if (!eregi ("^(10│172.16│192.168).", $ips[$i])) {

$ip = $ips[$i];

break;

}

}

}

return ($ip ? $ip : $_SERVER['REMOTE_ADDR']);

}

echo getRealIp();

// Get the user ip way 4

if ($HTTP_SERVER_VARS["HTTP_X_FORWARDED_FOR"])

{

$ip = $HTTP_SERVER_VARS["HTTP_X_FORWARDED_FOR"];

}

elseif ($HTTP_SERVER_VARS["HTTP_CLIENT_IP"])

{

$ip = $HTTP_SERVER_VARS["HTTP_CLIENT_IP"];

}

elseif ($HTTP_SERVER_VARS["REMOTE_ADDR"])

{

$ip = $HTTP_SERVER_VARS["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";

}

echo $ip ;

// Get the user ip way 5

if(getenv('HTTP_CLIENT_IP')) {

$onlineip = getenv('HTTP_CLIENT_IP');

} elseif(getenv('HTTP_X_FORWARDED_FOR')) {

$onlineip = getenv('HTTP_X_FORWARDED_FOR');

} elseif(getenv('REMOTE_ADDR')) {

$onlineip = getenv('REMOTE_ADDR');

} else {

$onlineip = $HTTP_SERVER_VARS['REMOTE_ADDR'];

}

echo $onlineip;