


How to Simulate a 404 Error and Display a Custom Error Page Using PHP?
Nov 11, 2024 pm 06:55 PMA PHP Guide to Creating Custom Error 404 Pages
In web development, handling errors is crucial for providing a seamless user experience. One common issue that developers face is creating custom error 404 pages, especially when using a .htaccess file for URL handling. This article addresses this specific scenario by explaining how to simulate an error 404 using PHP.
Problem Statement
The provided code using header($_SERVER["SERVER_PROTOCOL"]." 404 Not Found"); is not effectively triggering the 404 page configured in the .htaccess file. The question arises whether redirecting to the custom error 404 page is an incorrect approach.
Solution
To generate custom error 404 pages in PHP, it is recommended to use the http_response_code function introduced in PHP 5.4 and above:
<?php http_response_code(404); include('my_404.php'); // provide your own HTML for the error page die(); ?>
Explanation
- http_response_code(404) sets the HTTP response header to indicate an error 404 to the browser.
- include('my_404.php') includes the custom HTML for your error 404 page.
- die() terminates the script to prevent further execution and display the custom error page.
Advantages of Using http_response_code
- Proper HTTP Response: It sends the correct HTTP status code (404) to the browser, ensuring compatibility with web browsers and search engines.
- Flexibility: You can include custom HTML for your error page, allowing for tailored error messages and branding.
Conclusion
By employing the http_response_code function, you can effectively simulate an error 404 and display your custom error page when handling URLs that are not found in your internal endpoint script.
The above is the detailed content of How to Simulate a 404 Error and Display a Custom Error Page Using PHP?. For more information, please follow other related articles on the PHP Chinese website!

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