php中get_headers函數的作用及用法的詳細介紹

get_headers() 是PHP系統級函數，他返回一個包含有伺服器響應一個 HTTP 要求所發送的標題的數組。如果失敗則返回 FALSE 並發出一條 E_WARNING 層級的錯誤資訊(可用來判斷遠程檔案是否存在)。

函數定義

array get_headers ( string $url [, int $format = 0 ] )

參數

url 目標 URL

format 如果將可選的 format 參數設為 1，則 get_headers() 會解析相應的資訊並設定數組的鍵名。

樣本

<?php
$url='http://www.phpernote.com';
print_r(get_headers($url));
print_r(get_headers($url,1));
?>

以上常式的輸出類似於：

Array
(
[0] => HTTP/1.1 200 OK
[1] => Date: Sat, 29 May 2004 12:28:13 GMT
[2] => Server: Apache/1.3.27 (Unix) (Red-Hat/Linux)
[3] => Last-Modified: Wed, 08 Jan 2003 23:11:55 GMT
[4] => ETag: "3f80f-1b6-3e1cb03b"
[5] => Accept-Ranges: bytes
[6] => Content-Length: 438
[7] => Connection: close
[8] => Content-Type: text/html
)

Array
(
[0] => HTTP/1.1 200 OK
[Date] => Sat, 29 May 2004 12:28:14 GMT
[Server] => Apache/1.3.27 (Unix) (Red-Hat/Linux)
[Last-Modified] => Wed, 08 Jan 2003 23:11:55 GMT
[ETag] => "3f80f-1b6-3e1cb03b"
[Accept-Ranges] => bytes
[Content-Length] => 438
[Connection] => close
[Content-Type] => text/html
)