什么会使 XMLReader 可以通过命令行 `php` 使用，但不能通过 Apache 使用？

Question

Even the simplest PHP script I try to write, if I try to use XMLReader, will fail if I try and run it through localhost:

xml.php:

<?php $xmlReader = new XMLReader(); ?>

result (apache2/error.log):

Uncaught Error: Class 'XMLReader' not found in /var/www/html/xml.php:1

If I run the same script as above via the command line, php xml.php , there's no problem whatsoever. The XML library shows up in phpinfo() , and I'm told that PHP 7.2 doesn't have that flag that disables XMLReader (it stopped being default in 5.x). What else could be causing a breakdown?

I'm running Ubuntu 18.04, if that matters.

Answer 1

Since I had just installed php-xml , I had to restart my Apache service so that it could see the library:

sudo service apache2 restart

The command line was working because it was restarting with each call.

Always remember to restart your local server after installing vital components!