(PHP 5 >= 5.4.0, PHP 7)
header_register_callback — Call a header function
Registers a function that will be called when PHP starts sending output.
The callback is executed just after PHP prepares all
headers to be sent, and before any other output is sent, creating a window
to manipulate the outgoing headers before being sent.
callbackFunction called just before the headers are sent. It gets no parameters and the return value is ignored.
Gibt bei Erfolg TRUE zurück. Im Fehlerfall wird FALSE zurückgegeben.
Beispiel #1 header_register_callback() example
<?php
header('Content-Type: text/plain');
header('X-Test: foo');
function foo() {
foreach (headers_list() as $header) {
if (strpos($header, 'X-Powered-By:') !== false) {
header_remove('X-Powered-By');
}
header_remove('X-Test');
}
}
$result = header_register_callback('foo');
echo "a";
?>
Das oben gezeigte Beispiel erzeugt eine ähnliche Ausgabe wie:
Content-Type: text/plain a
header_register_callback() is executed just as the headers are about to be sent out, so any output from this function can break output.
Hinweis:
Header sind nur dann zugänglich und werden nur dann gesendet, wenn die genutzte SAPI sie unterstützt.