DEV Community

Md. Asif Rahman
Md. Asif Rahman

Posted on • Edited on

A real life example of using Late Static Binding in PHP.

Introduction:

In the world of software development, creating flexible and dynamic systems is most important. One essential feature of a dynamic system is the ability for subclasses to override and customize functionality inherited from a base class. In PHP, Late Static Binding is a powerful feature that enables this flexibility, allowing subclasses to access their own static properties and methods, even when called through the base class. In this article, we will explore the concept of Late Static Binding through a practical example of a dynamic database query system.

Understanding Late Static Binding:

Late Static Binding (LSB) is a feature in PHP that allows a child class to reference its parent class's static properties or methods using the static keyword. This feature opens the door to dynamic behavior within your classes. It's especially useful when dealing with inheritance and customization of functionality in subclasses.

The Scenario:

Consider a scenario where you are developing a web application with a database. You have a base Database class that contains common functionality for interacting with the database, such as querying and data retrieval. Additionally, you have two subclasses, User and Product, each representing a different entity in your application. These subclasses need to perform database queries specific to their respective tables.

Implementing Late Static Binding:

Let's dive into the code to see how Late Static Binding can help us achieve dynamic database queries:

<?php
class Database {
    protected static $tableName = '';

    public static function getTableName() {
        return static::$tableName;
    }

    public static function query() {
        $tableName = static::getTableName();
        return "SELECT * FROM $tableName";
    }
}

class User extends Database {
    protected static $tableName = 'users';
}

class Product extends Database {
    protected static $tableName = 'products';
}

//Example usage:
User::query(); // Outputs: SELECT * FROM users
Product::query(); // Outputs: SELECT * FROM products
Enter fullscreen mode Exit fullscreen mode

Explanation:

  1. In the Database class, we define a static property $tableName, which represents the name of the database table.

  2. The getTableName() method returns the table name using Late Static Binding with static::$tableName.

  3. The query() method constructs and returns a query string that includes the specific table name obtained using static::getTableName()

Conclusion:

Late Static Binding in PHP is a powerful tool that allows developers to create flexible and dynamic systems. In the example provided, we demonstrated how to use Late Static Binding to implement dynamic database queries in a web application. This feature empowers subclasses to access their own static properties and methods while maintaining a clear and organized class hierarchy. Incorporating Late Static Binding in your PHP applications can greatly enhance their flexibility and maintainability, ultimately leading to more robust and adaptable codebases.

Top comments (3)

Collapse
 
satyakr profile image
Satyajit Kumar

I think this selectAll(); should be query()

User::selectAll();
Product::selectAll();

Collapse
 
asifzcpe profile image
Md. Asif Rahman

@satyakr
Yes, my bad.
Thank you

Collapse
 
satyakr profile image
Satyajit Kumar

You're most wlcm bro 🤟