Question

I am getting started with OO PHP, and after reviewing a variety of classes which I have downloaded from the internet, I have noticed that some – but not all – of these classes have an intial function with the same name e.g.

class MyClass{

function MyClass{

//function contents in here

}

function otherfunction{

//more stuff here

}

}

What is this inital function for? And how does it help with writing classes?

Answer 1

It’s an old-style constructor. If you are using PHP 5 (you ought to), you should avoid those constructors and do instead:

class MyClass{

    function __construct() {
        //function contents in here
    }

    function otherfunction() {
        //more stuff here
    }
}

Constructors are, in short, used to run initialization code and enforce class invariants.