Hi,

How to Find a visitor's IP Address with PHP


Regards,
sivaraman

Hi,

In a PHP page, within the PHP tags, <?php ... ?>, you can retrieve the IP address of a user through the server variables array, which is contains information about the user and the server environment and is accessible from anywhere in your PHP script. To do this, you use the code $_SERVER['REMOTE_ADDR']. It works like a normal array, where REMOTE_ADDR is the key, and the IP address of the visitor is the value associated with that key.

Display The IP Address
So, if you want to display the IP Address to the user then the following page will suffice:

<?php
echo "Hello! Your IP Address is: " . $_SERVER['REMOTE_ADDR'];
?>

Exploring the $_SERVER array
You might be wondering what other information you can get from $_SERVER, well you can find out with the following script which displays all the variables in it along with their values if set, in a HTML table:

<table border="1">
<tr><th>Variable</th><th>Value</th></tr>
<?
foreach( $_SERVER as $key => $value )
{
echo "<tr><td>" . $key . "</td>";
echo "<td>" . $value . "</td></tr>";
}
?>
</table>

Finally, the following code works harder to find the true IP of the user by checking for proxies:

function userIP()
{
//This returns the True IP of the client calling the requested page
// Checks to see if HTTP_X_FORWARDED_FOR
// has a value then the client is operating via a proxy
$userIP = $_SERVER['HTTP_X_FORWARDED_FOR'];
if($userIP == "")
{
$userIP = $_SERVER['REMOTE_ADDR'];
}
// return the IP we've figured out:
return $userIP;
}

__________________
With,
J. Jeyaseelan
Everything Possible