PHP中获取当前页面完整的url

javascript实现：

top.location.href   顶级窗口的地址
this.location.href  当前窗口的地址

PHP实现

#测试网址:     http://localhost/blog/testurl.php?id=5 
//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);
#http://localhost/blog