getenv（“HTTP_XXX”）什么都不返回

Question

Why this code return "" :

$ip = "";
if(getenv("HTTP_CLIENT_IP")) 
{
 $ip = getenv("HTTP_CLIENT_IP");
} elseif(getenv("HTTP_X_FORWARDED_FOR")) {
 $ip = getenv("HTTP_X_FORWARDED_FOR");
} else {
 $ip = getenv("REMOTE_ADDR");
}

Environment: W2003EE, IIS 6.0, PHP 5.2.9 (ISAPI)

$_SERVER is a built-in PHP variable. getenv() looks at the current environment.

In my case i need to use $_SERVER. Thank all!

Answer 1

Try $_SERVER['REMOTE_ADDR'] or $_SERVER['HTTP_X_FORWARDED_FOR']

If you wonder what is set you can dump $_SERVER somewhere.