Error Handling in PHP: Simulating Error 404 for Non-Existent Pages
In your web application, you have implemented a custom URL handling mechanism using .htaccess to redirect requests to a specific PHP endpoint for processing. However, you are facing a challenge in simulating an Error 404 for pages that are not present in your database.
Solution: Using http_response_code
To correctly display a 404 error page, you must use the http_response_code function. This function sets the HTTP status code for the response, allowing you to specify that the requested page could not be found:
<?php http_response_code(404); include('my_404.php'); // Include your custom 404 error page die(); // Optional, but recommended to prevent further execution ?>
By setting the status code to 404, you inform the browser that the requested page does not exist, and it switches to display the error page you have configured using ErrorDocument in .htaccess.
Previous Approach: Redirection
Your previous attempt to simulate an error 404 using header was incorrect. Redirecting to another page (even your 404 error page) would lead to a 302 (Redirect) status code being sent to the browser, which is not appropriate for a non-existent page.
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