What are models in Codeigniter and how to write customized model?
Introduction
Codeigniter is an open-source web application framework for building dynamic, database-backed websites. It uses the PHP programming language to run on most common configurations of Linux and Unix-based operating systems. Codeigniter comes with a large library of pre-built components that allow you to build any type of website in a matter of minutes. However, it also provides functionality that allows you to create your own models and CRUD operations entirely from scratch! In this article we’ll cover how you can use methods and other features provided by Codeigniter’s API library to create custom models and CRUD actions on them.
Installing the model libraries
- Import the model libraries in the controller:
- $this->load->model(‘my_model’);
- Use the $this->load->model() function to load the model.
Creating a custom model class
The model class is used to store data and can be used in many different places. You can assign it to a controller, view file and custom function.
- Controller: The controller uses the model class for all of its actions. So if you need to save some data into it, then add an action method that will save the data using this method.
- View File: You need at least one view file which will show something based on your database table’s information (if any) or display error messages if there was any problem with saving or retrieving data from your database table(s). This is called as “View File”.
- Custom Function: A custom function allows you use logic based on what kind of validation rules are set up by default within CodeIgniter framework itself; otherwise we cannot use these types of functions unless we explicitly tell CodeIgniter what should happen when certain conditions are met by objects passed into them during execution time so that we don’t get errors later down line when trying again after some time has passed since last attempt failed due lack accessible resources needed at hand.”
Writing the logic for your model
In this section, we’ll cover the basics of writing logic for a model.
- The first thing you should know is that there are two ways to write code in CodeIgniter:
- Through the erb template system (and subsequently HTML): This is how most people write their models. The downside to this approach is that it needs to be styled using CSS before it can be viewed by visitors on your site or app frontend. You also don’t have access to all of CodeIgniter’s features when using this method because they’re not available in templates; however, if you need some functionality that isn’t available via templating, then this may still be the best option for you!
Making use of methods
Methods are a key part of how models work, and they can be used in many different ways. The most common use for methods is to add functionality to models. Methods can be used to validate data, add constraints or other constraints on your model, add pagination functionality and even views (in the case of the UserModel class).
Adding validation rules and constraints to models
Validation rules are used to validate incoming data. Constraints are used to define the data that is valid for a field. You can add validation rules and constraints to models using the $this->validate() function, as shown in the following example:
Codeigniter provides a lot of flexibility in creating models and making complex CRUD operations.
Codeigniter provides a lot of flexibility in creating models and making complex CRUD operations.
Creating a model is an easy process, as it’s just like creating any other array or dictionary object. You can use the following methods:
- new() – Creates an empty object with an ID property of 0 and the default value for all other properties (or None if they don’t exist). This method returns an instance of your class that you can use from within your controller or template files.
- load() – Loads data from another source into this class using its getter methods if provided (e.g., Model::load(mydata) ).
Conclusion
I hope you now have a better understanding of how you can use Codeigniter’s model libraries to create complex CRUD operations. The next step is to start building your own models and see how they work in practice. Remember that it’s always important to keep an eye on the naming conventions and make sure everything is consistent throughout your application.
