获取当前页面的完整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/dir/url.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']."
";

#/dir/url.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/dir/url.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/dir/url.php?id=5

//只取路径$url='http://'.$_SERVER['SERVER_NAME'].$_SERVER["REQUEST_URI"];
echo dirname($url);
#http://localhost/dir