How to get the URL in php

//获取域名或主机地址 echo $_SERVER['HTTP_HOST']."
"; #localhost //获取网页地址 echo $_SERVER['PHP_SELF']."
"; #/blog/testurl.php //获取网址参数 echo $_SERVER["QUERY_STRING"]."
"; #id=5 //获取用户代理 echo $_SERVER['HTTP_REFERER']."
"; //获取完整的url echo 'http://'.$_SERVER['HTTP_HOST'].$_SERVER['REQUEST_URI']; echo 'http://'.$_SERVER['HTTP_HOST'].$_SERVER['PHP_SELF'].'?'.$_SERVER['QUERY_STRING']; #http://localhost/blog/testurl.php?id=5 //包含端口号的完整url echo 'http://'.$_SERVER['SERVER_NAME'].':'.$_SERVER["SERVER_PORT"].$_SERVER["REQUEST_URI"]; # http ://localhost:80/blog/testurl.php?id=5 //只取路径 $url='http://'.$_SERVER['SERVER_NAME'].$_SERVER["REQUEST_URI"]; echo dirname($url);