This detailed guide offers a thorough overview of migrating from CodeIgniter 3 to CodeIgniter 4. It covers the major differences between the two versions, including architectural changes, new features, and deprecated functionalities. The article provides step-by-step instructions on how to adapt your existing CodeIgniter 3 application to the newer CodeIgniter 4 framework. Key topics include updating configuration files, refactoring code to align with new standards, and resolving compatibility issues. Additionally, it offers practical tips for taking advantage of CodeIgniter 4’s enhancements in performance, security, and modern PHP practices. Ideal for developers looking to upgrade their applications, this guide ensures a smooth and efficient transition to the latest version.
