PHP headers_list() function usage and example

PHP HTTP Reference Manual

The headers_list() function returns the sent HTTP response headers (or those ready to be sent)

Syntax

array headers_list(void)

Definition and usage

　headers_list() will return the HTTP response headers (or those ready to be sent) to the browser/Client HTTP header list. Check if these headers have been sent using headers_sent().

Return value

　Returns an array of header indices.

Online examples

<?php
/*　setcookie() will automatically add a response header　*/
setcookie('foo', 'bar');
/*　Add custom response headers
　Most clients will ignore this header automatically　*/
header("X-Sample-Test: foo
/*　Specify plain text content in the response text　*/
header('Content-type: text/plain');
/*　So what headers will be sent?　*/
var_dump(headers_list());
?>

Output result:

array(4) {
　　[0]=>
　　string(23) X-Powered-By: PHP/5.1.3
　　[1return
　　string(19) Set-Cookie: foo=bar"
　　[2return
　　string(18) X-Sample-Test: foo"
　　[3return
　　string(24) Content-type: text/plain"
}

PHP HTTP Reference Manual