สงสัยการเขียน php แบบ oop เรื่อง overloading override ครับ

function test(array $arr) {
    print_r($arr);
}

test(array(1, 2, 3)); // OK
test(555); // Fatal Error

<?php
function test(string $str) {
    echo $str;
}

test('Hello World'); // Fatal Error

<?php
function test(object $obj) {
    print_r($obj);
}

$o = new stdClass;
test($o); // Fatal Error

<?php
class object
{
}

function test(object $obj) {
    print_r($obj);
}

$o = new object;
test($o); // OK

<?php
class A
{

	public function test($a)
	{
	}

}

class B extends A
{

	public function test($b)
	{
	}

}

$b = new B();

<?php
class A
{

	public function test($a)
	{
	}

}

class B extends A
{

	public function test(array $a)
	{
	}

}

$b = new B();

class Mom{
public function test(){echo 'mom';}
}

class A extends Mom{
public function test(){echo 'a';}
}

class B {
public function test(){echo 'b';}
}

class C{
public function __construct(Mom $arg1){
$arg1->test();
}
}
$arr = array(new Mom, new A, new B);
new C($arr[0]);
new C($arr[1]);
new C($arr[2]); // error
// รวมถึง class property ที่เป็น public

<?php
class A
{

    public function __construct($a, $b, $c)
    {
        echo "$a,$b,$c";
    }

    public function test($a)
    {
        echo $a;
    }

}

class B extends A
{

    public function __construct($x)
    {
        parent::__construct($x, 2, 3);
    }

    public function test($a)
    {
        echo $a * $a;
    }

}

<?php
namespace jquery\ui\base;

class properties {
	public function __set($property, $value) {
		if (property_exists($this, 'property_'.$property)) {
			$property_name = 'property_'.$property;
			
			$this->$property_name = $value;
		} else if (property_exists($this, 'setonly_'.$property)) {
			$setonly_name = 'setonly_'.$property;
			
			$this->$setonly_name = $value;
		}
	}
	
	public function __get($property) {
		if (property_exists($this, 'property_'.$property))  {
			$property_name = 'property_'.$property;
			
			return $this->$property_name;
		} else if (property_exists($this, 'getonly_'.$property)) {
			$getonly_name = 'getonly_'.$property;
			
			return $this->$getonly_name;
		}
	}
}
?>

<?php
namespace jquery\ui;

spl_autoload_extensions('.php');
spl_autoload_register();

use jquery\phpclass\write as write;
use jquery\ui\base\properties as properties;

class calendar extends properties {
	protected $_control_id;
	protected $property_ajax = FALSE;
	protected $property_target = FALSE;
	   
	public function __construct($control_id) {
		$this->_control_id = $control_id;
	}
					
	public function create() {       
		write::line();
		write::formatln('<!-- ? -->', array($this->_control_id));
		write::line('<script type="text/javascript">');
		write::line('$(function() {', 1);
		write::formatln('$("#?_main").datepicker({', array($this->_control_id), 2);
		write::line('dateFormat: "d/m/yy",', 3);
		write::line('onSelect: function(date) {', 3);
		write::formatln('$("#?").val(date);', array($this->_control_id), 4);
		
		switch ($this->action()) {
			case 'JAVASCRIPT':
				write::formatln('if ($("#?").is("input"))',  array($this->property_target), 4);
				write::formatln('$("#?").val(date);',  array($this->property_target), 5);
				write::line('else', 4);
				write::formatln('$("#?").html(date);',  array($this->property_target), 5);
				break;
			case 'AJAX':
				write::line('$.ajax({', 4);
				write::formatln('url: "?",', array($this->property_ajax), 5);
				write::line('type: "POST",', 5);
				write::formatln('data: "?=" + $("#?").val(),', array($this->_control_id, $this->_control_id), 5);
				write::line('dataType: "html",', 5);
				write::line('global: false,', 5);
				write::line('async: false,', 5);
				write::line('cache: false,', 5);
				write::line('success: function(str) {', 5);
				write::formatln('if ($("#?").is("input"))',  array($this->property_target), 6);
				write::formatln('$("#?").val(str);',  array($this->property_target), 7);
				write::line('else', 6);
				write::formatln('$("#?").html(str);',  array($this->property_target), 7);
				write::line('}', 5);
				write::line('});', 4);
				break;
			default:
				write::formatln('$("#" + $("#?").closest("form").attr("id")).submit();', array($this->_control_id), 4);
				break;
		}
		
		write::line('}', 3);
		write::line('});', 2);
		write::line('});', 1);
		write::line('</script>');
		write::line();
		write::formatln('<div id="?_main"></div>', array($this->_control_id));
		write::formatln('<input type="hidden" id="?" name="?" />', array($this->_control_id, $this->_control_id));
		write::formatln('<!-- end ? -->', array($this->_control_id));
		write::line();                        
	}

	protected function action() {
		$result = 'POSTBACK';
		
		if ($this->property_ajax != FALSE)
			$result = 'AJAX';
		else if ($this->property_target != FALSE)
			$result = 'JAVASCRIPT';
		
		return $result;
	}
}
?>

<?php
        spl_autoload_extensions('.php');
        spl_autoload_register();

        use jquery\ui as ui;
?>

<!DOCTYPE html>

<html xmlns="http://www.w3.org/1999/xhtml">
	<head>
		<title>Jquery UI</title>
		<meta http-equiv="Content-Type" content="text/html;charset=utf-8" />
		<link type="text/css" rel="stylesheet" href="demos.css" />
		<?php  ui\script::startup(); ?>
	</head>
	<body>
		<form id="form1" name="form1" method="post">
			<div>
			<span>แบบ Postback:</span>
			<br />
			<?php
				$calendar1 = new ui\calendar('calendar1');
				$calendar1->create();
			?>
			<span id="result1"><?php if (!empty($_POST)) echo $_POST['calendar1']; ?></span>
			<br />
			<br />

			<span>แบบ Javascript:</span>
			<br />
			<?php
				$calendar2 = new ui\calendar('calendar2');
				$calendar2->target = 'result2';
				$calendar2->create();
			?>
			<span id="result2"></span>
			<br />
			<br />

			<span>แบบ Ajax:</span>
			<br />
			<?php
				$calendar3 = new ui\calendar('calendar3');
				$calendar3->ajax = 'ajax.php';
				$calendar3->target = 'result3';
				$calendar3->create();
			?>
			<span id="result3"></span>
			</div>
		</form>
	</body>
</html>