PHP Классы - 9 Наследование

[netcat-na-diary]

PHP Классы Наследование

Базовый класс. от которого наследуются два дочерних

<?php
	class ShopProduct {
		public $title;
		public $producerMainName;
		public $producerFirstName;
		public $price;
		public $numPages;
		public $playLength;
		
		function __construct ( $title, $firstName, $mainName, $price, $numPages = 0, $playLength = 0 )
		{
			$this->title = $title;
			$this->producerMainName = $mainName;
			$this->producerFirstName = $firstName;
			$this->price = $price;
			$this->numPages = $numPages;
			$this->playLength = $playLength;
		}
		
		function getProducer() {
			return "{$this->producerFirstName} "."{$this->producerMainName}";
		}
		
		function getSummaryLine() {
			$base = "$this->title ( {$this->producerMainName}, ";
			$base .= "{$this->producerFirstName})";
			return $base;
		}
	}

	class CDProduct extends ShopProduct {
		function getPlayLength() {
			return $this->playLength;
		}
		
		function getSummaryLine() {
			$base = "$this->title ( {$this->producerMainName}, ";
			$base .= "{$this->producerFirstName} )";
			$base .= ": Время звучания - {$this->playLength}";
			return $base;
		}
	}
	
	class BookProduct extends ShopProduct {
		function getNumberOfPages() {
			return $this->numPages;
		}
		
		function getSummaryLine() {
			$base = "$this->title ( {$this->producerMainName}, ";
			$base .= "{$this->producerFirstName} )";
			$base .= ": {$this->numPages} стр.";
			return $base;
		}
	}
?>

Переопределяем конструктор в дочерних классах

<?php
	class ShopProduct {
		public $title;
		public $producerMainName;
		public $producerFirstName;
		public $price;
		
		function __construct ( $title, $firstName, $mainName, $price )
		{
			$this->title = $title;
			$this->producerMainName = $mainName;
			$this->producerFirstName = $firstName;
			$this->price = $price;
		}
		
		function getProducer() {
			return "{$this->producerFirstName} "."{$this->producerMainName}";
		}
		
		function getSummaryLine() {
			$base = "$this->title ( {$this->producerMainName}, ";
			$base .= "{$this->producerFirstName})";
			return $base;
		}
	}

	class CDProduct extends ShopProduct {
		public $playLength;
		
		function __construct ( $title, $firstName, $mainName, $price, $playLength )
		{
			parent::__construct ( $title, $firstName, $mainName, $price );
			$this->playLength = $playLength;
		}
	
		function getPlayLength() {
			return $this->playLength;
		}
		
		function getSummaryLine() {
			$base = "$this->title ( {$this->producerMainName}, ";
			$base .= "{$this->producerFirstName} )";
			$base .= ": Время звучания - {$this->playLength}";
			return $base;
		}
	}
	
	class BookProduct extends ShopProduct {
		public $numPages;
		
		function __construct ( $title, $firstName, $mainName, $price, $numPages )
		{
			parent::__construct ( $title, $firstName, $mainName, $price );
			$this->numPages = $numPages;
		}
	
		function getNumberOfPages() {
			return $this->numPages;
		}
		
		function getSummaryLine() {
			$base = "$this->title ( {$this->producerMainName}, ";
			$base .= "{$this->producerFirstName} )";
			$base .= ": {$this->numPages} стр.";
			return $base;
		}
	}
	
	$product2 = new CDProduct ("Пропавший без вести", "Группа", "ДДТ", 10.99, null, 60.33);
	print "Исполнитель: {$product2->getProducer()}\n";
?>

Переопределим в дочерних классах методы, наследующие от родительского класса

<?php
	class ShopProduct {
		public $title;
		public $producerMainName;
		public $producerFirstName;
		public $price;
		
		function __construct ( $title, $firstName, $mainName, $price )
		{
			$this->title = $title;
			$this->producerMainName = $mainName;
			$this->producerFirstName = $firstName;
			$this->price = $price;
		}
		
		function getProducer() {
			return "{$this->producerFirstName} "."{$this->producerMainName}";
		}
		
		function getSummaryLine() {
			$base = "$this->title ( {$this->producerMainName}, ";
			$base .= "{$this->producerFirstName})";
			return $base;
		}
	}

	class CDProduct extends ShopProduct {
		public $playLength;
		
		function __construct ( $title, $firstName, $mainName, $price, $playLength )
		{
			parent::__construct ( $title, $firstName, $mainName, $price );
			$this->playLength = $playLength;
		}
	
		function getPlayLength() {
			return $this->playLength;
		}
		
		function getSummaryLine() {
			$base = parent::getSummaryLine();
			$base .= ": Время звучания - {$this->playLength}";
			return $base;
		}
	}
	
	class BookProduct extends ShopProduct {
		public $numPages;
		
		function __construct ( $title, $firstName, $mainName, $price, $numPages )
		{
			parent::__construct ( $title, $firstName, $mainName, $price );
			$this->numPages = $numPages;
		}
	
		function getNumberOfPages() {
			return $this->numPages;
		}
		
		function getSummaryLine() {
			$base = parent::getSummaryLine();
			$base .= ": {$this->numPages} стр.";
			return $base;
		}
	}
	
	$product2 = new CDProduct ("Пропавший без вести", "Группа", "ДДТ", 10.99, null, 60.33);
	print "Исполнитель: {$product2->getProducer()}\n";
?>

Изменить параметры доступа к свойствам и функциям

<?php
	class ShopProduct {
		private $title;
		private $producerMainName;
		private $producerFirstName;
		protected $price;
		private $discount = 0;
		
		public function __construct ( $title, $firstName, $mainName, $price )
		{
			$this->title = $title;
			$this->producerMainName = $mainName;
			$this->producerFirstName = $firstName;
			$this->price = $price;
		}
		
		public function getProducerFirstName () {
			return $this->producerFirstName;
		}
		
		public function getProducerMainName () {
			return $this->producerMainName;
		}
		
		public function setDiscount ( $num ) {
			$this->discount = $num;
		}
		
		public function getDiscount() {
			return $this->discount;
		}
		
		public function getTitle() {
			return $this->title;
		}
		
		public function getPrice() {
			return ($this->price - $this->discount);
		}
		
		public function getProducer() {
			return "{$this->producerFirstName} "."{$this->producerMainName}";
		}
		
		public function getSummaryLine() {
			$base = "$this->title ( {$this->producerMainName}, ";
			$base .= "{$this->producerFirstName})";
			return $base;
		}
	}

	class CDProduct extends ShopProduct {
		private $playLength;
		
		public function __construct ( $title, $firstName, $mainName, $price, $playLength )
		{
			parent::__construct ( $title, $firstName, $mainName, $price );
			$this->playLength = $playLength;
		}
	
		public function getPlayLength() {
			return $this->playLength;
		}
		
		public function getSummaryLine() {
			$base = parent::getSummaryLine();
			$base .= ": Время звучания - {$this->playLength}";
			return $base;
		}
	}
	
	class BookProduct extends ShopProduct {
		private $numPages;
		
		public function __construct ( $title, $firstName, $mainName, $price, $numPages )
		{
			parent::__construct ( $title, $firstName, $mainName, $price );
			$this->numPages = $numPages;
		}
	
		public function getNumberOfPages() {
			return $this->numPages;
		}
		
		public function getSummaryLine() {
			$base = parent::getSummaryLine();
			$base .= ": {$this->numPages} стр.";
			return $base;
		}
		
		public function getPrice() {
			return $this->price();
		}
	}
?>