终于写出个有用的东西了！

能够检测大部分通过代理服务器访问的ip.

<?php

//beiji.com2000.6.17

$ip = getenv("REMOTE_ADDR");

$v = getenv("HTTP_VIA");

$f = getenv("HTTP_X_FORWARDED_FOR");

$c = getenv("HTTP_XROXY_CONNECTION");

$o = getenv("HTTP_PRAGMA");

print '<br>REMOTE_ADDR';

print $ip;

if (($v=="")&&($f=="")&&($c=="")&&($o=="")){

print "<br>not through proxy";

}

else {

print "<br>through proxy";

print '<br>http_via: ';print $v;

print '<br>http_x_forwarded_for: ';print $f;

print '<br>http_xroxy_connection: ';print $c;

print '<br>http_pragma: ';print $o;

}

?>