Object Oriented Programming in PHP Explained in Detail

Object-Oriented Programming (OOPs) concept is the most important thing if you are thinking to start learning any back-end programming language. OOPs concepts are available in PHP also for complex coding.

What Is Object-Oriented Programming (OOP)?

Object-oriented programming is the programming language used to represent real-world entities using classes and objects.

It is the modern approach for solving real-world problems. In this method, the user focuses on an object while programming, not on the procedure.

As the user always deals with an object and performs operations on it, it brings the Object-oriented programming close to real-life using classes and objects.

What is the class in OOP?

The class is the blueprint of an object.
It contains all the information about an object.
It is a combination of variables and methods.

We can define a class using the class keyword.

Syntax 

class c_name{
// variables of class

// methods of class
}

Here first, we declare different variables of class, and then we declare and define the methods of a class.

For example, we want to create a class for the vehicle; we can do this as follows:

<?php
class Vehicle{
// variables
public $vtype;
public $color;
public $price;
public $speed;

// methods
public getdata($data){
// code
}
public setdata(){
// code
}
}
?>

Explanation

  • First, we declare the variables of class, such as vtype, color, price, and speed.
  • Next, we declare methods the getdata() and the setdata(), and inside these methods, we define the methods.

Here the class is the basic structure for all the objects of class vehicle. We can create different objects according to the requirement.

All the objects have the same variables and methods.

The class gives us the necessary information about an object by providing an answer for two questions as below:

  • How an object will behave?
  • What an object will contain?

So the class is the combination of the variables and procedures. Procedure use variables to define the activity of an object.
In this way, we can define all the real-world entities using classes such as a person, fruit, flower, animal, etc.

What is an object in OOP?

The object is an instance of the class.
It is a real-world entity.
We can create an object using the new keyword in PHP.

Syntax

class Classname{

// variables and methods

}

$objname = new Classname();

Here $objename is the name of an object, and Classname is the name of the class for which we want to create an object. We can create multiple objects of a class.

For example, we have a class vehicle as explained above, and we want to create an object of the class we can do this as follows:

<?php

class Vehicle{
// variables
public $vtype;
public $color;
public $price;
public $speed;

// methods
public getdata($data){
// code
}
public setdata(){
// code
}
}

$bike = new Vehicle();
?>

Explanation

  • First, we declare and define the class vehicle.
  • Next, we create an object of the class named $bike.

We can create as many objects as we want to create. There is no restriction on the amount of an object. All the objects have the same properties and methods defined in class but have different values.

Example of class and object:

Suppose we have a class vehicle having the variables vehicle type, color, and amount, and methods for getting data and setting values for them.

<!DOCTYPE html>
<html>
<body>

<?php
class Vehicle {
// Properties
public $vtype;
public $amount;
public $color;

// Methods
function set_vtype($vtype) {
$this->vtype = $vtype;
}
function get_vtype() {
return $this->vtype;
}
function set_amount($amount) {
$this->amount = $amount;
}
function get_amount() {
return $this->amount;
}
function set_color($color) {
$this->color = $color;
}
function get_color() {
return $this->color;
}
}

$bike = new Vehicle();
$bike->set_vtype('Gearless');
$bike->set_amount('50000');
$bike->set_color('Red');
echo "Vehicle type: " . $bike->get_vtype();
echo "<br>";
echo "Amount: " . $bike->get_amount();
echo "<br>";
echo "Color: " . $bike->get_color();
?>

</body>
</html>

Output

Vehicle type: Gearless
Amount: 50000
Color: Red

This is all about classes and objects in OOP using PHP. Object-oriented programming also having the following concepts, which are essential to understand how to use OOP efficiently.

  • Encapsulation
  • Inheritance
  • Polymorphism

Encapsulation

The binding of the properties to an object is called encapsulation.
It also a wrapping of some data into a single unit.
It is used for data hiding. It is mainly used for providing data security and reduce complexity.
It uses the get and set methods in PHP.

Inheritance

It is used to develop the relationship between the classes. It is the parent and child relationship. Here the child can use all the properties of the parent.
It uses the extend keyword.

For example, we have a class Person having the name and age property. We also have a class student and professor. Here we can inherit the properties of person class with student or professor class. It develops the parent-child relationship between them. It is mainly used for the reusability of the code multiple times in a program.

Polymorphism

It is the concept of having one form with different implementation methods. Here methods can be differentiated according to the type and numbers of the variables.
It uses implements keyword.

Conclusion

This all about OOPs concepts in PHP. We should have complete knowledge of how to use class and objects while coding for real-world problems. We should also consider inheritance and polymorphism to make the code reusable and more efficient.

I hope you found this post fully informative.

Thank you for reading 🙂

Leave a Reply

Your email address will not be published. Required fields are marked *

Read previous post:
hover css inline
Onhover Effect With Inline CSS and JavaScript

In most of the sites, you have noticed that when you hover the cursor on that text, it changes the...

Close