PHP multiple methods to obtain the real IP address of the client _ PHP Tutorial

PHP can be used to obtain the real IP address of the client. The code for copying an IP address function after complex judgment and calculation is as follows: functiongetIP () {if (getenv (HTTP_CLIENT_IP) {$ ipgetenv (HTTP_CLIENT_IP );} elseif (getenv (function for obtaining IP addresses after complicated judgment and calculation

The code is as follows:

Function getIP (){
If (getenv ('http _ CLIENT_IP ')){
$ Ip = getenv ('http _ CLIENT_IP ');
}
Elseif (getenv ('http _ X_FORWARDED_FOR ')){
$ Ip = getenv ('http _ X_FORWARDED_FOR ');
}
Elseif (getenv ('http _ x_forwarded ')){
$ Ip = getenv ('http _ x_forwarded ');
}
Elseif (getenv ('http _ FORWARDED_FOR ')){
$ Ip = getenv ('http _ FORWARDED_FOR ');

}
Elseif (getenv ('http _ forwarded ')){
$ Ip = getenv ('http _ forwarded ');
}
Else {
$ Ip = $ _ SERVER ['remote _ ADDR '];
}
Return $ ip;
}

The simplest example of getting an IP address code

The code is as follows:

$ ReIP = $ _ SERVER ["REMOTE_ADDR"];
Echo $ reIP;

Php ip retrieval algorithm

The code is as follows:

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;

Attackers can obtain IP addresses of internal and external websites.

The code is as follows:

Function getip_out (){
$ Ip = false;
If (! Empty ($ _ SERVER ["HTTP_CLIENT_IP"]) {
$ Ip = $ _ SERVER ["HTTP_CLIENT_IP"];
}
If (! Empty ($ _ SERVER ['http _ X_FORWARDED_FOR ']) {
$ Ips tutorial = 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 getip_out ();

What algorithm does php use to obtain ip addresses? Number expression to process

The code is as follows:

$ User_IP = ($ _ SERVER ["HTTP_VIA"])? $ _ SERVER ["HTTP_X_FORWARDED_FOR"]: $ _ SERVER ["REMOTE_ADDR"];
$ User_IP = ($ user_IP )? $ User_IP: $ _ SERVER ["REMOTE_ADDR"];

Function for obtaining the client IP address in php
Php obtains the real ip address of the client.

The response code is as follows: function getIP () {if (getenv ('http _ CLIENT_IP ') {$ ip = getenv ('http _ CLIENT_IP ');} elseif (getenv (...