[SOLVED] What can I do with this class?

[lopes_andre]

Hi,

 

I'am reading the book "PHP Objects, Patterns and Practice" and one of the examples in the book is this one:

 

<?php


class ShopProductWriter {
public $products = array();

public function addProduct( ShopProduct $shopProduct ) {
	$this->products[] = $shopProduct;
}

public function write() {
	$str = "";
	foreach ( $this->products as $shopProduct ) {
	$str .= "{$shopProduct->title}: ";
	$str .= $shopProduct->getProducer();
	$str .= " ({$shopProduct->getPrice()})\n";
	}
        print $str;
}
}

##########################################

class ShopProduct {
private $title;
private $producerMainName;
private $producerFirstName;
protected $price;
private $discount = 0;

public function __construct( $title, $firstName, $mainName, $price ) {
	$this->title = $title;
	$this->producerFirstName = $firstName;
	$this->producerMainName = $mainName;
	$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 = 0;

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();
	$base .= ": playing time - {$this->playLength}";
	return $base;
}
}




class BookProduct extends ShopProduct {

private $numPages = 0;

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();
	$base .= ": page count - {$this->numPages}";
	return $base;
}

public function getPrice() {
	return $this->price;
}
}


$produto = new ShopProduct("AA", "BB", "CC", "0");
echo $produto->getTitle();




?>

 

My question is: What does the class "ShopProductWriter" and how use it. In the book I don't see any explanation on on to use this class.

 

 

Best Regards,

André.

[ignace]

ShopProductWriter writes out your cart items. ShopProduct represents a product. You would use it like:

 

$spw = new ShopProductWriter();
$spw->addProduct(new ShopProduct('Product #1', 'Firstname', 'MainName', 'expensive'));
$spw->addProduct(new ShopProduct('Product #2', 'Firstname', 'MainName', 'expensive'));
$spw->addProduct(new ShopProduct('Product #3', 'Firstname', 'MainName', 'expensive'));
$spw->addProduct(new ShopProduct('Product #4', 'Firstname', 'MainName', 'expensive'));

print $spw->write();

 

I won't recommend using it on a production server (like it allows 'expensive' as a price..) though plus there are many things this class does not make advantage of (__toString(), ..).

[lopes_andre]

Thks, It worked!

 

I will not use this code in production. The code is only for educational purposes.

 

Best Regards,

André.

[twilitegxa]

Make sure you mark this post as solved if someone has answered your question :-)