PHP Basics (Section 5) - Object Oriented Programming

1. Prior to PHP5 OOP was a hack on top of the array implementation.
2. PHP5 changed eveything, in a great way.
3. Simple OO Example:

class person
{
public $age;
public $name;
function __construct($name, $age)
{
$this->name = $name;
$this->age = $age;
}
function birthday()
{
echo "Happy Birthday " . $this->name . "!";
$this->age++;
}
}

4. Public - Method or property can be accessed externally.
5. Private - Method or property is private to that class and can not be accessed externally.
6. Protected - Method or property is private and can also be accessed by extending classes
7. Final - Method can be overridden by extending classes.
8. Extending Example:

class friend extends person
{
private $relationship;
const MYNAME = "paul";
function __construct($name, $age, $relationship)
{
parent::__construct($name, $age);
$this->relationship = $relationship;
}
function showStatus()
{
echo "{$this->name} is my {$this->relationship}";
}
function fight()
{
$this->relationship = "enemy";
}
static function phoneCall()
{
echo friend::MYNAME . " the phone is for you";
}


9. Autoloading Example:

function __autoload($class_name)
{
require_once "/www/phpClasses/
{$class_name}.inc.php";
}
$a = new friend;

10. Special Functions: __construct(), __destruct(), __toString(), __sleep() __wakeup(), __call(), __get(), __set()
11. Design Patterns - Some time ago people realized that we were solving the same problems again and again, they then decided to sit down and come up with really good solutions to those problems, they’re called design patterns.
12. The advantages of design patterns are two fold: first they present a well defined solution to common problems, second they provide a common language for developers.