What is the $this in PHP OOP with Example?

In the OOP of PHP, there is a pseudo-variable called $this that refers to the current object. This pseudo-variable allows you to access the properties and methods of the current object within the class.

Use and Example of the PHP $this

In the code given in the following image, you can see there is a variable called $name whose value is 'John', and we try to access this variable inside the showName function.

But you can’t access like the following code, it does not work.

Now I will show you two ways to access the $name property inside the showname method.

First way to access the $name property

As we all know that, If you want to access the methods and properties of a class, first you have to create an instance or object of the class.

As you can see in the following code that we have created an instance $obj of the MyClass and we have passed the name through argument $obj->showName($obj->name).

<?php
class MyClass{
    public $name = 'John';

    public function showName($x){
        echo $x;
    }
}

$obj = new MyClass();

$obj->showName($obj->name);

---

Second way to access the $name property

Now we will use $this to access the $name property.

As you have already read in the above that $this refers to the current object, therefore you can access the $name property through the $this, but you have to use the object operator (->) with the $this.

<?php
class MyClass{
    public $name = 'John';

    public function showName(){
        echo $this->name;
    }
}

$obj = new MyClass();

$obj->showName();

---

Proof – current object and $this are equal

The current object and $this are equal, because the $this refers or pointing to the current object.

<?php
class MyClass{
    public $name = 'John';

    public function x(){
        return $this;
    }
}

$obj = new MyClass();

var_dump($obj === $obj->x());

bool(true)

---

Access methods using $this

You can also access the current object methods using the $this.

In the following given code you can see we accessing the process() method inside the addTwo() method using the $this.

<?php
class MyClass{
    private $num = 2;

    public function process(int $x){
        return $this->num + $x;
    }

    public function addTwo(int $x){
        // Accessing the process method using $this
        echo $this->process($x);
    }

}

$obj = new MyClass();

$obj->addTwo(5);

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