function getip() {
if (isset($_SERVER)) {
if (isset($_SERVER[HTTP_X_FORWARDED_FOR])) {
$realip = $_SERVER[HTTP_X_FORWARDED_FOR];
} elseif (isset($_SERVER[HTTP_CLIENT_IP])) {
$realip = $_SERVER[HTTP_CLIENT_IP];
} else {
$realip = $_SERVER[REMOTE_ADDR];
}
} else {
if (getenv(”HTTP_X_FORWARDED_FOR”)) {
$realip = getenv( “HTTP_X_FORWARDED_FOR”);
} elseif (getenv(”HTTP_CLIENT_IP”)) {
$realip = getenv(”HTTP_CLIENT_IP”);
} else {
$realip = getenv(”REMOTE_ADDR”);
}
}
return $realip;
2th:
1. function getip() {
2. if (isset($_SERVER)) {
3. /*在局域网通过透明代理访问外部的web服务器时,
*在web服务器端,
*通过header HTTP_X_FORWARDED_FOR 可以知道代理服务器的服务器名以及端口,
*/
4. if (isset($_SERVER[HTTP_X_FORWARDED_FOR])) {
5. $realip = $_SERVER[HTTP_X_FORWARDED_FOR];
6. } elseif (isset($_SERVER[HTTP_CLIENT_IP])) {
7. $realip = $_SERVER[HTTP_CLIENT_IP];
8. } else {
9. $realip = $_SERVER[REMOTE_ADDR];
10. }
11. } else {
12. /*string getenv ( string varname )*Returns the value of the environment variable varname, or FALSE on *an error.
13. */
14. if (getenv(“HTTP_X_FORWARDED_FOR”)) {
15. $realip = getenv( “HTTP_X_FORWARDED_FOR”);
16. } elseif (getenv(“HTTP_CLIENT_IP”)) {
17. $realip = getenv(“HTTP_CLIENT_IP”);
18. } else {
19. $realip = getenv(“REMOTE_ADDR”);
20. }
21. }
22. return $realip;
HTTP_X_FORWARDED_FOR获取的是最真实的,“HTTP_X_FORWARDED_FOR”是HTTP协议头中的一部分，也就是说客户端可以伪造，使用时需要进行相应检测防止被利用，例如网站有封IP的功能，恶意用户可以伪造IP，使网站误封正常用户的IP。
3th:
# class Client extends Object
# {
#
# /**
# * Gets the “true” IP address of the current user
# *
# * @return string the ip of the user
# */
# function getIp()
# {
# global ＄REMOTE_ADDR;
# global ＄HTTP_X_FORWARDED_FOR, ＄HTTP_X_FORWARDED, ＄HTTP_FORWARDED_FOR, ＄HTTP_FORWARDED;
# global ＄HTTP_VIA, ＄HTTP_X_COMING_FROM, ＄HTTP_COMING_FROM;
# global ＄HTTP_SERVER_VARS, ＄HTTP_ENV_VARS;
#
# // Get some server/environment variables values
# if (emptyempty(＄REMOTE_ADDR)) {
# if (!emptyempty(＄_SERVER) && isset(＄_SERVER['REMOTE_ADDR'])) {
# ＄REMOTE_ADDR = ＄_SERVER['REMOTE_ADDR'];
# }
# else if (!emptyempty(＄_ENV) && isset(＄_ENV['REMOTE_ADDR'])) {
# ＄REMOTE_ADDR = ＄_ENV['REMOTE_ADDR'];
# }
# else if (!emptyempty(＄HTTP_SERVER_VARS) && isset(＄HTTP_SERVER_VARS['REMOTE_ADDR'])) {
# ＄REMOTE_ADDR = ＄HTTP_SERVER_VARS['REMOTE_ADDR'];
# }
# else if (!emptyempty(＄HTTP_ENV_VARS) && isset(＄HTTP_ENV_VARS['REMOTE_ADDR'])) {
# ＄REMOTE_ADDR = ＄HTTP_ENV_VARS['REMOTE_ADDR'];
# }
# else if (@getenv(‘REMOTE_ADDR’)) {
# ＄REMOTE_ADDR = getenv(‘REMOTE_ADDR’);
# }
# } // end if
# if (emptyempty(＄HTTP_X_FORWARDED_FOR)) {
# if (!emptyempty(＄_SERVER) && isset(＄_SERVER['HTTP_X_FORWARDED_FOR'])) {
# ＄HTTP_X_FORWARDED_FOR = ＄_SERVER['HTTP_X_FORWARDED_FOR'];
# }
# else if (!emptyempty(＄_ENV) && isset(＄_ENV['HTTP_X_FORWARDED_FOR'])) {
# ＄HTTP_X_FORWARDED_FOR = ＄_ENV['HTTP_X_FORWARDED_FOR'];
# }
# else if (!emptyempty(＄HTTP_SERVER_VARS) && isset(＄HTTP_SERVER_VARS['HTTP_X_FORWARDED_FOR'])) {
# ＄HTTP_X_FORWARDED_FOR = ＄HTTP_SERVER_VARS['HTTP_X_FORWARDED_FOR'];
# }
# else if (!emptyempty(＄HTTP_ENV_VARS) && isset(＄HTTP_ENV_VARS['HTTP_X_FORWARDED_FOR'])) {
# ＄HTTP_X_FORWARDED_FOR = ＄HTTP_ENV_VARS['HTTP_X_FORWARDED_FOR'];
# }
# else if (@getenv(‘HTTP_X_FORWARDED_FOR’)) {
# ＄HTTP_X_FORWARDED_FOR = getenv(‘HTTP_X_FORWARDED_FOR’);
# }
# } // end if
# if (emptyempty(＄HTTP_X_FORWARDED)) {
# if (!emptyempty(＄_SERVER) && isset(＄_SERVER['HTTP_X_FORWARDED'])) {
# ＄HTTP_X_FORWARDED = ＄_SERVER['HTTP_X_FORWARDED'];
# }
# else if (!emptyempty(＄_ENV) && isset(＄_ENV['HTTP_X_FORWARDED'])) {
# ＄HTTP_X_FORWARDED = ＄_ENV['HTTP_X_FORWARDED'];
# }
# else if (!emptyempty(＄HTTP_SERVER_VARS) && isset(＄HTTP_SERVER_VARS['HTTP_X_FORWARDED'])) {
# ＄HTTP_X_FORWARDED = ＄HTTP_SERVER_VARS['HTTP_X_FORWARDED'];
# }
# else if (!emptyempty(＄HTTP_ENV_VARS) && isset(＄HTTP_ENV_VARS['HTTP_X_FORWARDED'])) {
# ＄HTTP_X_FORWARDED = ＄HTTP_ENV_VARS['HTTP_X_FORWARDED'];
# }
# else if (@getenv(‘HTTP_X_FORWARDED’)) {
# ＄HTTP_X_FORWARDED = getenv(‘HTTP_X_FORWARDED’);
# }
# } // end if
# if (emptyempty(＄HTTP_FORWARDED_FOR)) {
# if (!emptyempty(＄_SERVER) && isset(＄_SERVER['HTTP_FORWARDED_FOR'])) {
# ＄HTTP_FORWARDED_FOR = ＄_SERVER['HTTP_FORWARDED_FOR'];
# }
# else if (!emptyempty(＄_ENV) && isset(＄_ENV['HTTP_FORWARDED_FOR'])) {
# ＄HTTP_FORWARDED_FOR = ＄_ENV['HTTP_FORWARDED_FOR'];
# }
# else if (!emptyempty(＄HTTP_SERVER_VARS) && isset(＄HTTP_SERVER_VARS['HTTP_FORWARDED_FOR'])) {
# ＄HTTP_FORWARDED_FOR = ＄HTTP_SERVER_VARS['HTTP_FORWARDED_FOR'];
# }
# else if (!emptyempty(＄HTTP_ENV_VARS) && isset(＄HTTP_ENV_VARS['HTTP_FORWARDED_FOR'])) {
# ＄HTTP_FORWARDED_FOR = ＄HTTP_ENV_VARS['HTTP_FORWARDED_FOR'];
# }
# else if (@getenv(‘HTTP_FORWARDED_FOR’)) {
# ＄HTTP_FORWARDED_FOR = getenv(‘HTTP_FORWARDED_FOR’);
# }
# } // end if
# if (emptyempty(＄HTTP_FORWARDED)) {
# if (!emptyempty(＄_SERVER) && isset(＄_SERVER['HTTP_FORWARDED'])) {
# ＄HTTP_FORWARDED = ＄_SERVER['HTTP_FORWARDED'];
# }
# else if (!emptyempty(＄_ENV) && isset(＄_ENV['HTTP_FORWARDED'])) {
# ＄HTTP_FORWARDED = ＄_ENV['HTTP_FORWARDED'];
# }
# else if (!emptyempty(＄HTTP_SERVER_VARS) && isset(＄HTTP_SERVER_VARS['HTTP_FORWARDED'])) {
# ＄HTTP_FORWARDED = ＄HTTP_SERVER_VARS['HTTP_FORWARDED'];
# }
# else if (!emptyempty(＄HTTP_ENV_VARS) && isset(＄HTTP_ENV_VARS['HTTP_FORWARDED'])) {
# ＄HTTP_FORWARDED = ＄HTTP_ENV_VARS['HTTP_FORWARDED'];
# }
# else if (@getenv(‘HTTP_FORWARDED’)) {
# ＄HTTP_FORWARDED = getenv(‘HTTP_FORWARDED’);
# }
# } // end if
# if (emptyempty(＄HTTP_VIA)) {
# if (!emptyempty(＄_SERVER) && isset(＄_SERVER['HTTP_VIA'])) {
# ＄HTTP_VIA = ＄_SERVER['HTTP_VIA'];
# }
# else if (!emptyempty(＄_ENV) && isset(＄_ENV['HTTP_VIA'])) {
# ＄HTTP_VIA = ＄_ENV['HTTP_VIA'];
# }
# else if (!emptyempty(＄HTTP_SERVER_VARS) && isset(＄HTTP_SERVER_VARS['HTTP_VIA'])) {
# ＄HTTP_VIA = ＄HTTP_SERVER_VARS['HTTP_VIA'];
# }
# else if (!emptyempty(＄HTTP_ENV_VARS) && isset(＄HTTP_ENV_VARS['HTTP_VIA'])) {
# ＄HTTP_VIA = ＄HTTP_ENV_VARS['HTTP_VIA'];
# }
# else if (@getenv(‘HTTP_VIA’)) {
# ＄HTTP_VIA = getenv(‘HTTP_VIA’);
# }
# } // end if
# if (emptyempty(＄HTTP_X_COMING_FROM)) {
# if (!emptyempty(＄_SERVER) && isset(＄_SERVER['HTTP_X_COMING_FROM'])) {
# ＄HTTP_X_COMING_FROM = ＄_SERVER['HTTP_X_COMING_FROM'];
# }
# else if (!emptyempty(＄_ENV) && isset(＄_ENV['HTTP_X_COMING_FROM'])) {
# ＄HTTP_X_COMING_FROM = ＄_ENV['HTTP_X_COMING_FROM'];
# }
# else if (!emptyempty(＄HTTP_SERVER_VARS) && isset(＄HTTP_SERVER_VARS['HTTP_X_COMING_FROM'])) {
# ＄HTTP_X_COMING_FROM = ＄HTTP_SERVER_VARS['HTTP_X_COMING_FROM'];
# }
# else if (!emptyempty(＄HTTP_ENV_VARS) && isset(＄HTTP_ENV_VARS['HTTP_X_COMING_FROM'])) {
# ＄HTTP_X_COMING_FROM = ＄HTTP_ENV_VARS['HTTP_X_COMING_FROM'];
# }
# else if (@getenv(‘HTTP_X_COMING_FROM’)) {
# ＄HTTP_X_COMING_FROM = getenv(‘HTTP_X_COMING_FROM’);
# }
# } // end if
# if (emptyempty(＄HTTP_COMING_FROM)) {
# if (!emptyempty(＄_SERVER) && isset(＄_SERVER['HTTP_COMING_FROM'])) {
# ＄HTTP_COMING_FROM = ＄_SERVER['HTTP_COMING_FROM'];
# }
# else if (!emptyempty(＄_ENV) && isset(＄_ENV['HTTP_COMING_FROM'])) {
# ＄HTTP_COMING_FROM = ＄_ENV['HTTP_COMING_FROM'];
# }
# else if (!emptyempty(＄HTTP_COMING_FROM) && isset(＄HTTP_SERVER_VARS['HTTP_COMING_FROM'])) {
# ＄HTTP_COMING_FROM = ＄HTTP_SERVER_VARS['HTTP_COMING_FROM'];
# }
# else if (!emptyempty(＄HTTP_ENV_VARS) && isset(＄HTTP_ENV_VARS['HTTP_COMING_FROM'])) {
# ＄HTTP_COMING_FROM = ＄HTTP_ENV_VARS['HTTP_COMING_FROM'];
# }
# else if (@getenv(‘HTTP_COMING_FROM’)) {
# ＄HTTP_COMING_FROM = getenv(‘HTTP_COMING_FROM’);
# }
# } // end if
#
# // Gets the default ip sent by the user
# if (!emptyempty(＄REMOTE_ADDR)) {
# ＄direct_ip = ＄REMOTE_ADDR;
# }
#
# // Gets the proxy ip sent by the user
# ＄proxy_ip = ‘;
# if (!empty(＄HTTP_X_FORWARDED_FOR)) {
# ＄proxy_ip = ＄HTTP_X_FORWARDED_FOR;
# } else if (!empty(＄HTTP_X_FORWARDED)) {
# ＄proxy_ip = ＄HTTP_X_FORWARDED;
# } else if (!empty(＄HTTP_FORWARDED_FOR)) {
# ＄proxy_ip = ＄HTTP_FORWARDED_FOR;
# } else if (!empty(＄HTTP_FORWARDED)) {
# ＄proxy_ip = ＄HTTP_FORWARDED;
# } else if (!empty(＄HTTP_VIA)) {
# ＄proxy_ip = ＄HTTP_VIA;
# } else if (!empty(＄HTTP_X_COMING_FROM)) {
# ＄proxy_ip = ＄HTTP_X_COMING_FROM;
# } else if (!empty(＄HTTP_COMING_FROM)) {
# ＄proxy_ip = ＄HTTP_COMING_FROM;
# } // end if… else if…
#
# // Returns the true IP if it has been found, else FALSE
# if (empty(＄proxy_ip)) {
# // True IP without proxy
# return ＄direct_ip;
# } else {
# ＄is_ip = ereg(’^([0-9]{1,3}.){3,3}[0-9]{1,3}‘, ＄proxy_ip, ＄regs);
# if (＄is_ip && (count(＄regs) > 0)) {
# // True IP behind a proxy
# return ＄regs[0];
# } else {
# // Can’t define IP: there is a proxy but we don‘t have
# // information about the true IP
# return FALSE;
# }
# } // end if… else…
# } // end of the ‘PMA_getIp()’ function
# }