Effortlessly redirect to another page using PHP
Table of contents:
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How to perform a redirection
-
Understanding the code
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The anatomy of a HTTP response
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301 or 302? How to choose the kind of redirection with PHP?
How to perform a redirection
To redirect to another page using PHP, run the following code:
// We make sure no text is echoed before we set the header. header('Location: https://example.com'); exit;Understanding the code
- We make sure no text has been echoed before setting the header. We don’t want to pollute our response. Continue reading if you want to know what I’m talking about.
- Then, using the
header()function, we set a header that will inform the visitor’s browser that its user needs to be redirect to another page. What’s a header? I’ll explain later. - Finally, we stop the execution of the code using
exit. This isn’t mandatory, but this isn’t necessary either. It’s just common practice.
Basically, using HTTP, the server running your PHP code respond to your visitor’s browser and asks it to redirect its user to the URL you provided.
The anatomy of a HTTP response
Let me show you an example HTTP response, which is how a web server communicates with the browser:
HTTP/1.1 302 Found Content-Type: text/htmlLocation: https://example.com <html> <p>This is a redirection.</p></html>Weird, right? But this is easy. Here’s how a response is constructed:
- The status line containing:
- The version of HTTP used by the server.
- The status code.
- The reason phrase for the status code.
- The headers. We can see our
Locationheader holding the URL to which we want to redirect the visitor. - The body, carrying the HTML of your web page. For a redirect, HTML is usually not needed, though.
Also, do you remember when I talked about not polluting our response? Well, echoing text before using the header() in PHP will add whatever text you like in it, which can have side effects.
301 or 302? How to choose the kind of redirection with PHP?
The header() function in PHP lets you choose which kind of redirect you perform. By default, it’s creates a 302 Found redirection:
header('Location: https://example.com');Here’s the HTTP response sent on my local machine:
HTTP/1.1 302 FoundServer: nginx/1.25.1Date: Tue, 19 Sep 2023 18:08:31 GMTContent-Type: text/html; charset=UTF-8Transfer-Encoding: chunkedConnection: closeX-Powered-By: PHP/8.2.10Location: https://example.comTo make it a 301 Moved Permanently kind of redirection, you can leverage the header() function third argument: $response_code:
header('Location: https://example.com', response_code: 301);Which sends a HTTP response that looks like this:
HTTP/1.1 301 Moved PermanentlyServer: nginx/1.25.1Date: Tue, 19 Sep 2023 18:13:01 GMTContent-Type: text/html; charset=UTF-8Transfer-Encoding: chunkedConnection: closeX-Powered-By: PHP/8.2.10Location: https://example.com
