Why Doesn't My PHP `ini_set('upload_max_filesize')` Work as Expected?

Troubleshooting upload_max_filesize Modification in PHP

When encountering inconsistencies between the intended and observed values of upload_max_filesize, it's crucial to investigate potential causes. Here's a closer examination of the issue:

Original Code and Behavior:

<?php
ini_set('upload_max_filesize', '10M');
echo ini_get('upload_max_filesize'), ", ", ini_get('post_max_size');
?>

Upon execution, this code outputs "2M, 8M" despite the php.ini settings being:

upload_max_filesize = 10M
post_max_size = 10M

Potential Causes:

1. Shorthand Notation:
   In PHP, the use of shorthand notation for configuration values is restricted to PHP.ini itself. Attempting to set values using this notation outside of PHP.ini may cause unexpected behavior, such as the fallback to default values.
2. Unsupported Setting:
   upload_max_filesize is reportedly a PHP_INI_PERDIR setting, meaning it cannot be modified using ini_set(). The official list of PHP directives confirms this.

Solution:

• Ensure that PHP.ini contains the correct values for upload_max_filesize and post_max_size.
• Use numeric values instead of shorthand notation when setting these values in PHP.ini.
• Restart the web server (e.g., Apache) after modifying PHP.ini to ensure the changes take effect.

Once these corrections are made, the code should reflect the expected behavior and allow for file uploads up to the specified limit.

The above is the detailed content of Why Doesn't My PHP `ini_set('upload_max_filesize')` Work as Expected?. For more information, please follow other related articles on the PHP Chinese website!