Question

I’m a newbie implementing OOP in PHP. For PHP project, I often use codeigniter framework. Currently, I face a problem in designing classes for my own library.
Here is the description:

class ABC{
        function A(){

        }
        function B(){

        }
        function C(){

        }
}
class XYZ{
        function A(){

        }
        function similarToB(){

        }
        function X(){

        }
}

Class ABC and XYZ have similar features. Function A is shared between both classes. Function B from class ABC is similar to function similarToB from class XYZ (they have the same name and parameter, but different implementation). Function C is totally different from function X. There may be also another similar classes.
What is the best way to design those classes (e.g. using inheritance, interface, etc)?

Answer 1

My Recommendation:

class ancestor { 
    public function A() { }
}

interface BInterface { 
    public function B();
}

class ABC extends ancestor implements BInterface {
    public function B() { }
    public function C() { }
}

class XYZ extends ancestor implements BInterface {
    public function B() { }
    public function X() { }
}

I know everyone is going to give you the “it depends” shtick (and it really does depend on what you want to do), but I think this is what you are looking for.