PHP中獲取當前頁面的完整URL和部分URL

javascript實現：

top.location.href 頂級窗口的地址

this.location.href 當前窗口的地址

#測試網址: http://localhost/blog/testurl.php?id=5

//獲取域名或主機地址

echo $_SERVER['HTTP_HOST']."<br>"; #localhost

//獲取網頁地址

echo $_SERVER['PHP_SELF']."<br>"; #/blog/testurl.php

//獲取網址參數

echo $_SERVER["QUERY_STRING"]."<br>"; #id=5

//獲取用戶代理

echo $_SERVER['HTTP_REFERER']."<br>";

//獲取完整的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

//包含端口號的完整url

echo 'http://'.$_SERVER['SERVER_NAME'].':'.$_SERVER["SERVER_PORT"].$_SERVER["REQUEST_URI"];

#http://localhost:80/blog/testurl.php?id=5

//只取路徑

$url='http://'.$_SERVER['SERVER_NAME'].$_SERVER["REQUEST_URI"];

echo dirname($url);

#http://localhost/blog