Constructor in PHP OOP with example

Posted 9 years ago By Ajay Gupta 117620

Constructor in PHP with example ?

Constructor is a key part of PHP oops concept.
Constructor in PHP is special type of function of a class which is automatically executed as any object of that class is created or instantiated.
Constructor is also called magic function because in PHP, magic method is start usually with two underscore characters.
In PHP4, we create constructor by class name it means the name of constructor is same as the class name but in PHP5, it has been changed to create constructor, it can be initialized by `__construct` keyword.

Why do we need a constructor ?

As we know constructor is a special function and it automatically called when any object of a class is instantiated, so in that way we can take benefits of constructor by using it in our class. We can setup the object before using it, or can start session in constructor so we don't have to start in every method of class.
You can write some line of code and start to instantiate an object to call class method then constructor called as object is instantiated and the line of code which is written in constructor is executed automatically.
Constructor with parameters is look like regular method because you can pass the variable to constructor as in regular method.

                            
class Bird
{
    
    public $bird_name = "No any birds for now";
    
    public function __construct($bird_name)
    {
        $this->bird_name = $bird_name;
    }
}
$bird = new Bird("Sparrow is bird"); // now constructor is called automatically because we have initialized the object or class Bird.
echo $bird->bird_name;
Output of above code is :
Sparrow is bird

                            class Bird{        public $bird_name = "No any birds for now";        public function __construct($bird_name)    {        $this->bird_name = $bird_name;    }}$bird = new Bird("Sparrow is bird"); // now constructor is called automatically because we have initialized the object or class Bird.echo $bird->bird_name;Output of above code is :Sparrow is bird