HTTP Header: HTTP headers are the code that transfers the data between web server and browser. The HTTP headers are mainly intended for the communication between the server and the client in both directions.
HTTP Request Header: When type a URL in the address bar of browser and try to access it, the browser sends an HTTP request to the server. The HTTP request header contains information in a text-record form, which includes many useful informations such as the type, capabilities, and version of the browser that generates the request, the operating system used by the client, the page that was requested, the various types of outputs accepted by the browser, and so on. Receiving the request header, the web server will send an HTTP response header back to the client.
Read any request header: It can be achieved by using getallheaders() function.
Example 1:
<?php foreach (getallheaders() as $name => $value) { Â Â Â Â echo "$name: $value <br>"; } ?> |
Output:
Host: 127.0.0.3:2025 Connection: keep-alive Cache-Control: max-age=0 Upgrade-Insecure-Requests: 1 User-Agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.67 Safari/537.36 Accept: text/html, application/xhtml+xml, application/xml;q=0.9, image/webp, image/apng, */*;q=0.8 Accept-Encoding: gzip, deflate, br Accept-Language: en-US, en;q=0.9
Example 2: It can be achieved by using apache_request_headers() function.
<?php $header = apache_request_headers(); Â Â foreach ($header as $headers => $value) { Â Â Â Â echo "$headers: $value <br />\n"; } ?> |
Host: 127.0.0.6:2027 Connection: keep-alive Cache-Control: max-age=0 Upgrade-Insecure-Requests: 1 User-Agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.67 Safari/537.36 Accept: text/html, application/xhtml+xml, application/xml;q=0.9, image/webp, image/apng, */*;q=0.8 Accept-Encoding: gzip, deflate, br Accept-Language: en-US, en;q=0.9
Reference: http://php.net/manual/en/function.header.php
