**What is the __construct function and how does it work in OOP?**

Understanding the __construct Function in OOP

As a beginner in Object-Oriented Programming (OOP), you may have encountered the term "__construct" used in conjunction with classes. This function plays a crucial role in initializing and setting up objects when they are created.

Purpose of __construct

Introduced in PHP 5, __construct is the designated method for defining constructors in classes. A constructor is a special method that is automatically executed when an object is instantiated. It allows you to perform any necessary setup operations, such as initializing properties or connecting to external resources.

Example Usage

Let's consider an example in PHP to demonstrate the usage of __construct:

<code class="php">class Database {
  protected $userName;
  protected $password;
  protected $dbName;

  public function __construct($userName, $password, $dbName) {
    $this->userName = $userName;
    $this->password = $password;
    $this->dbName = $dbName;
  }
}</code>

In this example, the Database class has three properties, userName, password, and dbName. When an object of this class is created, the __construct constructor is invoked, and the values of userName, password, and dbName are assigned accordingly.

To instantiate the Database object and utilize the __construct function, you would use the following syntax:

<code class="php">$db = new Database('user_name', 'password', 'database_name');</code>

Upon object creation, the values provided to the __construct method are assigned to the corresponding properties, thus initializing the database connection details.

For more in-depth information, refer to the PHP manual linked here: [PHP Manual - Constructors and Destructors](https://www.php.net/manual/en/language.oop5.decon.php)

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