看一下$_SERVER['REQUEST_URI']，即

$actual_link = "http://$_SERVER[HTTP_HOST]$_SERVER[REQUEST_URI]";

(注意双引号字符串语法是完全正确的)

如果你想同时支持HTTP和HTTPS，你可以使用

$actual_link = (isset($_SERVER['HTTPS']) && $_SERVER['HTTPS'] === 'on' ? "https" : "http") . "://$_SERVER[HTTP_HOST]$_SERVER[REQUEST_URI]";

编者注:使用此代码具有安全隐患。客户端可以将HTTP_HOST和REQUEST_URI设置为它想要的任意值。

你可以使用不带参数的http_build_url来获取当前页面的完整URL:

$url = http_build_url();

清晰的代码，工作在所有的web服务器(Apache, nginx, IIS，…)

$url = (isset($_SERVER['HTTPS']) && $_SERVER['HTTPS'] !== 'off' ? 'https' : 'http') . '://' . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI'];

你可以使用HTTP_ORIGIN，如下面的代码片段所示:

if ( ! array_key_exists( 'HTTP_ORIGIN', $_SERVER ) ) {
    $this->referer = $_SERVER['SERVER_NAME'];
} else {
    $this->referer = $_SERVER['HTTP_ORIGIN'];
}

    public static function getCurrentUrl($withQuery = true)
    {
        $protocol = (!empty($_SERVER['HTTPS']) && strtolower($_SERVER['HTTPS']) !== 'off')
        or (isset($_SERVER['HTTP_X_FORWARDED_PROTO']) && strtolower($_SERVER['HTTP_X_FORWARDED_PROTO']) === 'https')
        or (!empty($_SERVER['HTTP_FRONT_END_HTTPS']) && strtolower($_SERVER['HTTP_FRONT_END_HTTPS']) !== 'off')
        or (isset($_SERVER['SERVER_PORT']) && intval($_SERVER['SERVER_PORT']) === 443) ? 'https' : 'http';

        $uri = $protocol . '://' . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI'];

        return $withQuery ? $uri : str_replace('?' . $_SERVER['QUERY_STRING'], '', $uri);
    }

这是你问题的解决方案:

//Fetch page URL by this

$url = $_SERVER['REQUEST_URI'];
echo "$url<br />";

//It will print
//fetch host by this

$host=$_SERVER['HTTP_HOST'];
echo "$host<br />";

//You can fetch the full URL by this

$fullurl = "http://".$_SERVER['HTTP_HOST'].$_SERVER['REQUEST_URI'];
echo $fullurl;