Are abstract class constructors not implicitly called when a derived class is instantiated?

abstract-class, php

Solution

No, the constructor of the parent class is not called if the child class defines a constructor.

From the constructor of your child class, you have to call the constructor of the parent's class :

parent::__construct();

Passing it parameters, if needed.

Generally, you'll do so at the beginning of the constructor of the child class, before any specific code ; which means, in your case, you'd have :

class Child extends Base {
    function __construct() {
        parent::__construct();
        echo 'Child __construct<br/>';
    }
}

And, for reference, you can take a look at this page of the PHP manual : Constructors and Destructors -- it states (quoting) :

Note: Parent constructors are not called implicitly if the child class defines a constructor. In order to run a parent constructor, a call to `parent::__construct()` within the child constructor is required.

Problem

Take this example: ``` abstract class Base { function __construct() { echo 'Base __construct<br/>'; } } class Child extends Base { function __construct() { echo 'Child __construct<br/>'; } } $c = new Child(); ``` Coming from a C# background, I expect the output to be Base __construct Child __construct However, the actual output is just Child __construct

Original source