Constructor in PHP

In PHP, a constructor is a special method that gets called automatically when an object is created from a class. It is used to initialize the properties of the object.

To create a constructor in PHP, you define a method with the same name as the class, preceded by double underscores (__construct).

Here's an example of a class with a constructor:

class Person {
  public $name;
  public $age;
  
  public function __construct($name, $age) {
    $this->name = $name;
    $this->age = $age;
  }
  
  public function greet() {
    echo "Hello, my name is " . $this->name . " and I am " . $this->age . " years old.";
  }
}
$person = new Person("John", 30);

$person->greet(); // Output: Hello, my name is John and I am 30 years old.

In this example, the constructor takes two parameters ($name and $age) and initializes the corresponding properties of the object using the $this keyword. The greet() method simply outputs a string containing the person's name and age.

When we create a new Person object, we pass in two arguments (John and 30) that are used to initialize the object's properties. Finally, we call the greet() method on the object to output the person's name and age.