Using preg_replace_callback with external class

Question

I have a question for you!

Normally, if you call a callback function within an OOP context you have to use array(&$this, \'callback_function\')

Answer 1

Say your external class looks like this

If your callback function makes no reference to $this, you can call it statically like so:

preg_replace_callback($pattern, 'ExternalClass::callback', $subject);

Otherwise, your method should work in theory.

preg_replace_callback($pattern, array(new ExternalClass, 'callback'), $subject);

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