How to use variable from one controller in another in opencart?

Question

PHP

I want to include a variable from one controller to another, the iclude_once method and then use the variable for some reason does not work

Answer 1

What exactly does this variable do?
Use Registry to pass variables/objects between classes.
You most likely have incorrectly built the logic of work, because this is a rather strange task.
Describe your initial task.