How to call model variables in laravel

Laravel is a popular PHP framework that provides a powerful Model-View-Controller (MVC) architecture for quickly building web applications. In Laravel, models are the core part of managing application data. This article will explore how to call model variables in Laravel.

In Laravel, there are two main types of model variables: instance variables and static variables. Instance variables belong to a specific model instance and are defined in the model. Static variables are defined within the model class and are not associated with any specific model instance. Let us discuss the implementation of these two variables separately.

Instance variables

Instance variables are usually used to store attributes of the model, such as fields in a database table. In Laravel, how to define and access instance variables in a model? For example, suppose we have a User model that defines a property named name. We can create a basic constructor in the model class to specify a default value for the name attribute.

<?php
 
namespace AppModels;
 
use IlluminateDatabaseEloquentModel;
 
class User extends Model
{
    public $name;
 
    public function __construct()
    {
        $this->name = 'John Doe';
    }
}

Then, in the controller or anywhere else, we can instantiate a User object and access the object's name property:

$user = new User;
$name = $user->name; // 'John Doe'

Pretty simple, right? We can also get or set instance variables through access methods. For example, we can add a getName method to the model to get the value of the name attribute:

public function getName()
{
    return $this->name;
}

Then, we can call this method to get the value of the instance variable:

$user = new User;
$name = $user->getName(); // 'John Doe'

We can also pass set method to set the value of instance variables:

public function setName($name)
{
    $this->name = $name;
}

Then, we can call this method to set the value of instance variables:

$user = new User;
$user->setName('Jane Doe');
$name = $user->getName(); // 'Jane Doe'

Static variables

Static variables are in the model Defined in a class and not associated with any specific model instance. Static variables are typically used to store information related to the model class itself, such as whether soft deletion is enabled for the model class. In Laravel, how to define and access static variables in the model?

We can define a static variable in the model class like this:

<?php
 
namespace AppModels;
 
use IlluminateDatabaseEloquentModel;
 
class User extends Model
{
    public static $softDeleteEnabled = true;
 
    // ...
}

Then we can access that static variable in the controller or any other place:

$softDeleteEnabled = User::$softDeleteEnabled; // true

Static variables can be accessed through the self or static keyword in the class. If we want to access static variables in the model class, we can use the self keyword:

class User extends Model
{
    public static $softDeleteEnabled = true;
 
    public function isSoftDeleteEnabled()
    {
        return self::$softDeleteEnabled;
    }
}

Then, we can call this method to check the value of the static variable:

$user = new User;
$softDeleteEnabled = $user->isSoftDeleteEnabled(); // true

If we want to To access static variables in a class, you can use the static keyword:

class Admin extends User
{
    public function isSoftDeleteEnabled()
    {
        return static::$softDeleteEnabled;
    }
}

Now, we can instantiate an Admin object and call the isSoftDeleteEnabled method to check the value of the static variable:

$admin = new Admin;
$softDeleteEnabled = $admin->isSoftDeleteEnabled(); // true

Conclusion

In Laravel, models are the core part of managing application data. Instance variables and static variables are two common model variables. Instance variables are typically used to store attributes of a model, such as fields in a database table. Static variables are used to store information related to the model class itself. In this article, we explored how to define and access these two types of variables in Laravel. Mastering this knowledge allows us to better understand and develop Laravel applications.

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