php 获取当前页面地址

//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);

/**
 * 获取当前页面地址
 *
 * @author 111cn.net
 */
function getPageUrl() {
 $pageURL = 'http';

 if ($_SERVER["HTTPS"] == "on") {
  $pageURL .= "s";
 }
 $pageURL .= "://";

 if ($_SERVER["SERVER_PORT"] != "80") {
  $pageURL .= $_SERVER["SERVER_NAME"] . ":" . $_SERVER["SERVER_PORT"] . $_SERVER["REQUEST_URI"];
 } else {
  $pageURL .= $_SERVER["SERVER_NAME"] . $_SERVER["REQUEST_URI"];
 }
 return $pageURL;
}