url相关
#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
//获取本机ip地址
echo $_SERVER["REMOTE_ADDR"];die;
//获取网页地址
echo$_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'].$_SERVER["REQUEST_URI"];
echodirname($url);
#http://localhost/blog
$arr = pathinfo($url);
var_dump($arr);die;