(PHP 8 >= 8.4.0)
http_get_last_response_headers — Retrieve last HTTP response headers
   Returns an array containing the last HTTP
   response headers received via the
   HTTP wrapper.
   If there are none, null is returned instead.
  
此函数没有参数。
   Returns an indexed array of HTTP headers
   which were received while using the
   HTTP wrapper.
   If there are none, null is returned instead.
  
示例 #1 http_get_last_response_headers() example
Description.
<?php
file_get_contents("http://example.com");
var_dump(http_get_last_response_headers());
?>以上示例的输出类似于:
array(14) {
  [0]=>
  string(15) "HTTP/1.1 200 OK"
  [1]=>
  string(20) "Accept-Ranges: bytes"
  [2]=>
  string(11) "Age: 326940"
  [3]=>
  string(29) "Cache-Control: max-age=604800"
  [4]=>
  string(38) "Content-Type: text/html; charset=UTF-8"
  [5]=>
  string(35) "Date: Mon, 11 Nov 2024 13:34:09 GMT"
  [6]=>
  string(23) "Etag: "3147526947+gzip""
  [7]=>
  string(38) "Expires: Mon, 18 Nov 2024 13:34:09 GMT"
  [8]=>
  string(44) "Last-Modified: Thu, 17 Oct 2019 07:18:26 GMT"
  [9]=>
  string(24) "Server: ECAcc (nyd/D16C)"
  [10]=>
  string(21) "Vary: Accept-Encoding"
  [11]=>
  string(12) "X-Cache: HIT"
  [12]=>
  string(20) "Content-Length: 1256"
  [13]=>
  string(17) "Connection: close"
}
