On Elated.com today there's the fourth part of their series looking at object oriented programming in PHP. This time the focus is specifically on autoloading classes, making objects into strings (serialized) and introspection.

If you've read all the articles up to this point then you're already familiar with the most important concepts of object-oriented programming in PHP: classes, objects, properties, methods, and inheritance. In this final (for now, at least!) tutorial in the series, I'm going to tie up some loose ends and look at some other useful OOP-related features of PHP.

He looks at each of the three topics above and includes code for things like a simple autoloader, object serialization, using sleep/wakeup and an example of using functions like get_class, get_class_methods and get_object_vars to do introspection on your classes and objects.