PHP Get Domain Name method

Method one (with system variables)

Disadvantages do not use delivered addresses and hosts that do not support system variables

echo $_server[' Http_host '];

Method two (with its own function)

$url = ' http://www.51php.net/index.php?referer=51php.net ';

$arr _url = Parse_url ($url);

echo $arr _url[' host '];

Method Three (write your own function)

function GetDomain ($url)

{

$url = Str_replace (' http://', ', ', $url); If there is an HTTP prefix, remove the

$pos = Strpos ($url, '/');

if ($pos = = False)

{

return $url;

}else

{

Return substr ($url, 0, $pos);

}

}

echo GetDomain ($url);

Method IV (with regular)

Preg_match ("/^" (http://)? [^/]+)/I ", $url, $arr _domain);

echo $arr _domain[2];