Apache - PHP SERVER_ADDR显示内部IP？

echo $_SERVER['SERVER_ADDR'] always yields 192.168.1.142, which is the IP address of my server within my home network. I can access the website using my external IP since I've set up the port forward on my router, but $_SERVER['SERVER_ADDR'] will only return the internal IP, no matter what I try.

How can I make $_SERVER['SERVER_ADDR'] return my external IP?

You can use file_get_contents function for this. You just need to find a host which can return your ip address

$externalContent = file_get_contents('http://checkip.dyndns.com/');
preg_match('/Current IP Address: ([\[\]:.[0-9a-fA-F]+)</', $externalContent, $myIp);
echo $myexternalIp = $myIp[1];

Add a second IP to your server (ifconfig eth0:1 192.168.1.143) and use that in your router's port forwarding rules. That way, external accesses will be coming in through that address instead and you can tell the difference between the two.