#测试网址:     http://localhost/blog/testurl.php?id=5//获取域名或主机地址 echo $_SERVER[‘HTTP_HOST‘]."<br>"; #localhost//获取网页地址 echo $_SERVER[‘PHP_SELF‘]."<br>"; #/blog/testurl.php//获取网址参数 echo $_SERVER["QUERY_STRING"]."<br>"; #id=5//获取用户代理 echo $_SERVER[‘HTTP_REFERER‘]."<br>"; //获取完整的urlecho ‘http://‘.$_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urlecho ‘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);#http://localhost/blog