TIL the header() function in PHP that sends raw HTTP headers to a client.
header() must be called before any actual output is sent (or called), either by normal HTML tags, blank lines in a file or from PHP. For example:
<?php
header("X-Content-Type-Options: nosniff");
header("X-Frame-Options: DENY");
header("X-XSS-Protection: 1; mode=block");
header("Referrer-Policy: no-referrer-when-downgrade");
?>
<!doctype html>
<html lang="en">
<head>
...Syntax
void header ( string $string [, bool $replace = true [, int $http_response_code ]] )| Parameter | Description |
|---|---|
string |
required - Specifies the header string to send |
replace |
optional - Indicates whether the header should replace previous or add a second header; default is true (will replace); false (allows multiple headers of the same type) |
http_response_code |
optional - Forces the HTTP response code to the specified value |
Documentation
See the documentation for more details.
