Xtremefaith Xtremefaith - 2 months ago 14
PHP Question

PHP Autoloading Extended Classes

Based on the response from this question I would expect my code to work but for some reason it is not. I have a simple class that extends a class from my library of classes.

_custom.php

$custom = new MyClass();
class MyClass extends MyAbstractClass{

public function __construct(){
parent::__construct();
}

}


Unfortunately I get this fatal error:


Fatal error: Class 'MyClass' not found in ...


But if I remove the
extends MyAbstractClass
then the error goes away. It seems the issue is that when attempting to extend the class, it does not attempt to load
MyAbstactClass
which then causes
MyClass
to not be found at all.

Any thoughts or suggestions on this?

Answer

PHP is an interpreted language, meaning that what is known for PHP to define is the code that parsed before a statement.

class MyClass extends MyAbstractClass{

  public function __construct(){
      parent::__construct(); #you are forcing a construct call, it is not required if the parent constructor has no args.
  }

}

$custom = new MyClass();

With classes you can prevent this behavior by using an autoloader, when an object is called and is undefined, it will try to inject and parse the class by your given code.

You can define the magic function __autoload() but the spl_autoload_register() is preferred as it is more dynamic and not a constant as the __autoload() function is.