CodeIgniter is an open-source framework that uses the MVC (Model-View-Controller) model to help developers save time while building fully functional websites and apps using PHP.
Among all PHP frameworks, CodeIgniter is the quickest. Users can choose from several different versions of CodeIgniter.
CodeIgniter 3 and CodeIgniter 4 are the most stable of the other versions:
The CodeIgniter framework provides you with an out-of-the-box database and basic operations libraries, such as sending emails, file uploading, session management, and so on.
CodeIgniter 4 is the latest edition of the CodeIgniter framework, and it is now ready for production use. With this new edition, there is a lot of anticipation. As a result, coders were anxiously awaiting this release.
The earlier version of CodeIgniter was based on PHP 5.6 or below, but CodeIgniter 4 now includes PHP 7.2 compatibility and capabilities. If you plan to perform a CURL Request in CI4, you must first install the lib curl library.
Command-line programming is also supported by CI 4. According to current trends, most frameworks include CLI usability and a library.
As a result, CodeIgniter 4 has implemented this functionality as well, and you can now utilize the command line in the most recent version of CI. MySQL (5.1+), PostgreSQL, and SqLite3 are some common supported Databases by CodeIgniter.
CI 4 now includes a public folder that serves as your app’s document root. CI 4 now has its own server, like Laravel, which you can start using PHP spark serve.
The following techniques can be used to install CodeIgniter 4:
You may manually install CI 4 by downloading the current version from its official website and extracting it to your server’s root directory.
– If you need to utilize the Composer tool, you’ll need to install it first, then use the command line to launch it. In the future, Composer will help you include third-party plugins in your project. This link will allow you to download and install the composer: https://getcomposer.org/.
– You may also grab the CodeIgniter file from the CI 4 git repository. To access it, click the link and download it to your root directory: https://github.com/bcit-ci/CodeIgniter.
Big changes in CodeIgniter 4:
The structure of the files is different in CI 4 than in CI 3. The structure of CodeIgniter 4 is structured into five directories: /app, /system, /public, /writable, and/tests.
Instead of CI Controller, you need to extend \CodeIgniter\Controller in CodeIgniter 4.
The new feature in CI4 is the ability to interact with Request and Response objects: It’s more effective than the CI3 method. If you want to utilize your controller as a Base Controller, you may build it in any place you want and then extend Controller to use it everywhere you want.
In CI4 the model must extend \CodeIgniter \Model. Automated database connection, basic CRUD, in-model validation, and automatic pagination are all new features in the CI4 model. View cells in CI4 allow you to create your response in pieces.
The .env files are natively supported by CodeIgniter 4, allowing for the optimization of the settings of the many contexts in which it may be used (production, tests, development).
In terms of performance, CodeIgniter 4 outperforms CodeIgniter 3 in terms of using PHP 7 in writing and as a server minimal setup, among other things.
It is incompatible with CodeIgniter’s previous version. So, if you want to utilize CodeIgniter 4, you’ll have to put in a little more work to keep it up to update. Since it was extremely easy to update in previous versions, but they have introduced a lot of new features in this update, which is why it is not compatible with the oldest version of CodeIgniter.
To conclude, CodeIgniter4 has a better possibility of establishing itself effectively, because practically all the previous versions’ flaws have been addressed, and now the software has been completely rewritten.