PHP guru, please help. You'll get 30.00 USD$ - GoFuckYourself.com

etech · 03-04-2005, 01:05 AM

Im writing a singleton pattern for a shopping basket.
But it keeps creating a new instance of the class when im calling Basket::getInstance();
What do i do wrong, i searched everywhere on google.

30$ to the guy that figure this out.

<?php
class Basket
{
private static $instance = null;
private $liste;

private function __construct()
{

$this->liste = array();
}

public static function &getInstance()
{
if(self::$instancehahahahanull)
{
echo "opretter instance".rand(1,10000);
self::$instance = new Basket();
}

return self::$instance;
}

public function pushProduct($object)
{
array_push($this->liste,$object);
}

public function popProduct($object)
{
$newListe = array();
for($i=0; $i<count($this->liste);$i++)
{
if($this->liste[$i]!=$object)
{
array_push($newListe,$this->liste[$i]);
}
}
$this->liste = $newListe;
}

public function getList()
{
return $this->liste;
}
}
?>

This is my main method

<?php
include_once("class/Basket.php");
$basket = Basket::getInstance();
$basket->pushProduct($object);
?>

calmlikeabomb · 03-04-2005, 01:19 AM

So you are just trying to create a variable that is storing the products and quantity that the user will be purchasing ?

How about using a server side session ?

Let me know if I'm following you here.

etech · 03-04-2005, 05:03 AM

Quote:

Originally Posted by calmlikeabomb

So you are just trying to create a variable that is storing the products and quantity that the user will be purchasing ?

How about using a server side session ?

Let me know if I'm following you here.

Yes i am, it crossed my mind. and will work ofcourse.
Its just that its better to know some wellknown patterns.

lilspup · 03-04-2005, 07:15 AM

Perhaps you should change self::$instancehahahahanull to self::$instance?

calmlikeabomb · 03-04-2005, 12:18 PM

Ok, well let's try a using a session.

This can be your addcart.php or whatever.

http://www.name.com/add.php?id=6

Where 6 is the product we are adding to the basket.

Code:

session_start();// start the session

if (is_numeric ($_GET['pid'])) { // Check for a product ID.

	$pid = $_GET['pid'];// Product ID being added to cart

if (isset ($_SESSION['cart'][$pid])) {// don't allow user to add twice
echo '<p>This item has already been added to your shopping cart!</p>';
exit();
		
} else {// If the product isn't part of the session add it.
$qty = 1;
}

	// Add to the cart session variable.
	$_SESSION['cart'][$pid] = $qty;

}//end if check for a product

That variable will hold all of your product ID's and a quantity of 1.

If you want to allow the item to be added to the cart more than 1 time.
Find and Replace:

Code:

echo '<p>This item has already been added to your shopping cart!</p>';
exit();

with:

Code:

$_SESSION['cart'][$pid] +1;

You can use this variable on your view cart page to retrieve what's in the user cart session.

etech · 03-05-2005, 10:14 AM

I know it will work with saving the data in a Session. But is it impossible wo get a singleton working ? I dont get it, cause alot of sites is talking about how great it is, that you can make a singleton on php5

03-04-2005, 01:05 AM	#1
etech Confirmed User Join Date: Feb 2004 Location: Right next to you.... Posts: 1,148	PHP guru, please help. You'll get 30.00 USD$ Im writing a singleton pattern for a shopping basket. But it keeps creating a new instance of the class when im calling Basket::getInstance(); What do i do wrong, i searched everywhere on google. 30$ to the guy that figure this out. <?php class Basket { private static $instance = null; private $liste; private function __construct() { $this->liste = array(); } public static function &getInstance() { if(self::$instancehahahahanull) { echo "opretter instance".rand(1,10000); self::$instance = new Basket(); } return self::$instance; } public function pushProduct($object) { array_push($this->liste,$object); } public function popProduct($object) { $newListe = array(); for($i=0; $i<count($this->liste);$i++) { if($this->liste[$i]!=$object) { array_push($newListe,$this->liste[$i]); } } $this->liste = $newListe; } public function getList() { return $this->liste; } } ?> This is my main method <?php include_once("class/Basket.php"); $basket = Basket::getInstance(); $basket->pushProduct($object); ?>

03-04-2005, 01:19 AM	#2
calmlikeabomb Confirmed User Join Date: May 2004 Location: SW Palm Bay, Florida Posts: 1,323	So you are just trying to create a variable that is storing the products and quantity that the user will be purchasing ? How about using a server side session ? Let me know if I'm following you here. __________________ subarus.

03-04-2005, 12:18 PM	#5
calmlikeabomb Confirmed User Join Date: May 2004 Location: SW Palm Bay, Florida Posts: 1,323	Ok, well let's try a using a session. This can be your addcart.php or whatever. http://www.name.com/add.php?id=6 Where 6 is the product we are adding to the basket. Code: session_start();// start the session if (is_numeric ($_GET['pid'])) { // Check for a product ID. $pid = $_GET['pid'];// Product ID being added to cart if (isset ($_SESSION['cart'][$pid])) {// don't allow user to add twice echo '<p>This item has already been added to your shopping cart!</p>'; exit(); } else {// If the product isn't part of the session add it. $qty = 1; } // Add to the cart session variable. $_SESSION['cart'][$pid] = $qty; }//end if check for a product That variable will hold all of your product ID's and a quantity of 1. If you want to allow the item to be added to the cart more than 1 time. Find and Replace: Code: echo '<p>This item has already been added to your shopping cart!</p>'; exit(); with: Code: $_SESSION['cart'][$pid] +1; You can use this variable on your view cart page to retrieve what's in the user cart session. __________________ subarus.

03-04-2005, 07:15 AM	#4
lilspup Confirmed User Industry Role: Join Date: Aug 2004 Location: Portland, Oregon Posts: 716	Perhaps you should change self::$instancehahahahanull to self::$instance?

03-05-2005, 10:14 AM	#6
etech Confirmed User Join Date: Feb 2004 Location: Right next to you.... Posts: 1,148	I know it will work with saving the data in a Session. But is it impossible wo get a singleton working ? I dont get it, cause alot of sites is talking about how great it is, that you can make a singleton on php5