On Sun, Jul 15, 2012 at 5:50 AM, shiplu <shiplu.net@xxxxxxxxx> wrote: > From OOP point of view. > > Use encapsulation: > When a class has a "has-a" relation-ship with other class you should use > encapsulation. For example, If MyDB is a class that "has-a" pdo driver in > it, then PDO will be encapsulated inside MyDB class. This is also called > containment. MyDB should contain PDO. > > Use inheritance: > When a class has a "is-a" relation ship with other class use inheritance. > For example, Dog is an Animal. so Dog should extend Animal class. MyPHPDb > is-a PHP Database Object (aka PDO). So it'll be inheritance. MyPHPDb should > extend PDO. > > Think about the relation have. Then implement it. > > > -- > Shiplu.Mokadd.im > ImgSign.com | A dynamic signature machine > Innovation distinguishes between follower and leader > Yes, good: "has-a" and "is-a". In some cases, the distinction seems clear. The think in this case, the class I'm implementing "has-a" PDO driver, rather than "is-a" PDO driver. In this case, I'm encapsulting the PDO classes within my class to provide removal of details from the main program for dealing with data, which isn't particularly interested in how that data is manipulated or stored. -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
