How to use Codeigniter with other framework?

I would like to use the database classes and methods in other PHP frameworks. I have an idea if I include the autolader from vendor it will work, but I can't find a tutorial about that. Could anyone please help me?

I think you need to choose a framework. They are not generally designed to inter-operate.

I chose to move from Laravel because I was not using many of the included features and it appears slow to my clients. I ended up choosing Codeigniter due to its light weight and speed. For my needs, we really need to move a longer term supported release including patches but without breaking changes. The current reading changes and file changes can be daunting, especially if your enterprise project is several releases behind,

This might be helpful.
https://github.com/kenjis/ci4-session-in-plain-php

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This might be helpful.
https://github.com/kenjis/ci4-session-in-plain-php

It is still not enough. I am trying to get inside autoload vendor.

1. Install "codeigniter4/framework" via Composer.
2. add dependencies (constants, functions, etc.) in somewhere when needed.

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1. Install "codeigniter4/framework" via Composer.
2. add dependencies (constants, functions, etc.) in somewhere when needed.

Let me try another time. Suppose you want to use CI4 in another framework that does not support composer autoloader. I am a noob at this. But I can understand that there are class path that I can use. But I don't know the class names or the namespaces. Have you heard of Eloquent from Laravel. We can use this independently anywhere.

All you have to do is:
1. Before using a class or function, load the class or function definition.
2. Before using a constant, define the constant.
So this is not difficult (but may be bothersome) if you know how to use PHP.

CI4 follows PSR-4, so if you have or write a PSR-4 autoloader, it can autoload class files.
CI4 uses namespace "CodeIginter". See https://github.com/codeigniter4/CodeIgni...on#L63-L65

If there is something missing to load/define, PHP raises an error. So you just the load/define missing things.

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