echo $_SERVER['HTTP_HOST']."<br>";
echo $_SERVER['PHP_SELF']."<br>";
echo $_SERVER["QUERY_STRING"]."<br>";
echo $_SERVER['HTTP_REFERER']."<br>";
echo $_SERVER["REQUEST_SCHEME"].'://'.$_SERVER['HTTP_HOST'].$_SERVER['REQUEST_URI'];
echo $_SERVER["REQUEST_SCHEME"].'://'.$_SERVER['HTTP_HOST'].$_SERVER['PHP_SELF'].'?'.$_SERVER['QUERY_STRING'];
echo $_SERVER["REQUEST_SCHEME"].'://'.$_SERVER['SERVER_NAME'].':'.$_SERVER["SERVER_PORT"].$_SERVER["REQUEST_URI"];
$url='http://'.$_SERVER['SERVER_NAME'].$_SERVER["REQUEST_URI"];
echo dirname($url);