PHP seems to have undefined variables

willow

Hi everyone, new to all this so please bare with me.

I have been running some tests on PHP Ajax shopping carts and have encountered the following problem - I will deal with the simpler version for now as the 2 I am running [seem] to have the same problem:

I have the following page script running (CSS stipped here out to make it smaller):

<?php

// INCLUDE JCART BEFORE SESSION START
include 'jcart/jcart.php';

// START SESSION
session_start();

// INITIALIZE JCART AFTER SESSION START
$cart =& $_SESSION['jcart']; if(!is_object($cart)) $cart = new jcart();

?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
	<head>
		<meta http-equiv="content-type" content="text/html; charset=utf-8" />

	<title>jCart - Free Ajax/PHP shopping cart</title>


	<link rel="stylesheet" type="text/css" media="screen, projection" href="jcart/jcart.css" />

</head>
<body>
	<div id="wrapper">
		<h2>Demo Store</h2>

		<div id="sidebar">
			<?php $cart->display_cart($jcart);?>
		</div>

		<div id="content">
			<form method="post" action="" class="jcart">
				<fieldset>
					<input type="hidden" name="my-item-id" value="1" />
					<input type="hidden" name="my-item-name" value="Soccer Ball" />
					<input type="hidden" name="my-item-price" value="25.00" />

					<ul>
						<li><strong>Soccer Ball</strong></li>
						<li>Price: $25.00</li>
						<li>
							<label>Qty: <input type="text" name="my-item-qty" value="1" size="3" /></label>
						</li>
					</ul>

					<input type="submit" name="my-add-button" value="add to cart" class="button" />
				</fieldset>
			</form>

			<form method="post" action="" class="jcart">
				<fieldset>
					<input type="hidden" name="my-item-id" value="2" />
					<input type="hidden" name="my-item-name" value="Baseball Mitt" />
					<input type="hidden" name="my-item-price" value="19.50" />

					<ul>
						<li><strong>Baseball Mitt</strong></li>
						<li>Price: $19.50</li>
						<li>
							<label>Qty: <input type="text" name="my-item-qty" value="1" size="3" /></label>
						</li>
					</ul>

					<input type="submit" name="my-add-button" value="add to cart" class="button" />
				</fieldset>
			</form>

			<form method="post" action="" class="jcart">
				<fieldset>
					<input type="hidden" name="my-item-id" value="3" />
					<input type="hidden" name="my-item-name" value="Hockey Stick" />
					<input type="hidden" name="my-item-price" value="33.25" />

					<ul>
						<li><strong>Hockey Stick</strong></li>
						<li>Price: $33.25</li>
						<li>
							<label>Qty: <input type="text" name="my-item-qty" value="1" size="3" /></label>
						</li>
					</ul>

					<input type="submit" name="my-add-button" value="add to cart" class="button" />
				</fieldset>
			</form>

			<div class="clear"></div>
		</div>
	</div>

	<script type="text/javascript" src="jcart/jquery-1.3.2.min.js"></script>
	<script type="text/javascript" src="jcart/jcart-javascript.min.php"></script>
</body>
</html>

When this page (store.php) is run locally using MAMP on a Apple Mac i get no error messages and it seems to work fine, however, when uploaded to a windows server and load the page I get the following error messages:

Notice: Undefined index: my-item-id in E:\domains\c\client.ask-design.co.uk\user\htdocs\jcart\jcart\jcart.php on line 248

Notice: Undefined index: my-item-qty in E:\domains\c\client.ask-design.co.uk\user\htdocs\jcart\jcart\jcart.php on line 249

Notice: Undefined index: my-item-price in E:\domains\c\client.ask-design.co.uk\user\htdocs\jcart\jcart\jcart.php on line 250

On and on.....

Any ideas why this should be so anyone.

The uploaded file can be found here:

http://www.client.ask-design.co.uk/jcart/store.php

Cheers,

Regards,

Willow.

bradgrafelman

Welcome to PHPBuilder!

When posting PHP code, please use the board's [noparse]

..

[/noparse] bbcode tags as they make your code much easier to read and analyze.

willow wrote:
When this page (store.php) is run locally using MAMP on a Apple Mac i get no error messages and it seems to work fine

That would suggest that you either a) don't have display_errors turned on, or b) don't have error_reporting set to at least E_ALL (IMHO, this should be the minimum error reporting level when developing).

willow wrote:
Any ideas why this should be so anyone.

Well, you didn't show us the PHP script that's generating the errors, but my guess is that it's referring to things such as $_POST['my-item-id'] without verifying that those variables exist first. You should always use something like [man]empty/man or [man]isset/man before accessing external data.

In other words, this is bad:

$id = $_POST['my-item-id'];

while this is better:

$id = (isset($_POST['my-item-id']) ? $_POST['my-item-id'] : NULL);

willow

Thought I would post the code that is called in on the store.php page if this will help:

<?php


include_once('jcart-config.php');

include_once('jcart-defaults.php');

class jcart {
	var $total = 0;
	var $itemcount = 0;
	var $items = array();
	var $itemprices = array();
	var $itemqtys = array();
	var $itemname = array();

function cart() {}

function get_contents()
	{
	$items = array();
	foreach($this->items as $tmp_item)
		{
		$item = FALSE;

		$item['id'] = $tmp_item;
		$item['qty'] = $this->itemqtys[$tmp_item];
		$item['price'] = $this->itemprices[$tmp_item];
		$item['name'] = $this->itemname[$tmp_item];
		$item['subtotal'] = $item['qty'] * $item['price'];
		$items[] = $item;
		}
	return $items;
	}

function add_item($item_id, $item_qty=1, $item_price, $item_name)
	{

	$valid_item_qty = $valid_item_price = false;

	if (preg_match("/^[0-9-]+$/i", $item_qty))
		{
		$valid_item_qty = true;
		}

	if (is_numeric($item_price))
		{
		$valid_item_price = true;
		}

	if ($valid_item_qty !== false && $valid_item_price !== false)
		{

		if($this->itemqtys[$item_id] > 0)
			{
			$this->itemqtys[$item_id] = $item_qty + $this->itemqtys[$item_id];
			$this->_update_total();
			}

		else
			{
			$this->items[] = $item_id;
			$this->itemqtys[$item_id] = $item_qty;
			$this->itemprices[$item_id] = $item_price;
			$this->itemname[$item_id] = $item_name;
			}
		$this->_update_total();
		return true;
		}

	else if	($valid_item_qty !== true)
		{
		$error_type = 'qty';
		return $error_type;
		}
	else if	($valid_item_price !== true)
		{
		$error_type = 'price';
		return $error_type;
		}
	}

function update_item($item_id, $item_qty)
	{

	if (preg_match("/^[0-9-]+$/i", $item_qty))
		{
		if($item_qty < 1)
			{
			$this->del_item($item_id);
			}
		else
			{
			$this->itemqtys[$item_id] = $item_qty;
			}
		$this->_update_total();
		return true;
		}
	}

function update_cart()
	{

	if (is_array($_POST['jcart_item_ids']))
		{

		$item_ids = implode($_POST['jcart_item_ids']);
		}

	if (is_array($_POST['jcart_item_qty']))
		{

		$item_qtys = implode($_POST['jcart_item_qty']);
		}

	if ($_POST['jcart_item_id'])
		{

		if (preg_match("/^[0-9-]+$/i", $item_qtys) || $item_qtys == '')
			{

			$count = 0;


			foreach ($_POST['jcart_item_id'] as $item_id)
				{

				$update_item_qty = intval($_POST['jcart_item_qty'][$count]);

				if($update_item_qty < 1)
					{
					$this->del_item($item_id);
					}
				else
					{

					$this->update_item($item_id, $update_item_qty);
					}

				$count++;
				}
			return true;
			}
		}

	else if (!$_POST['jcart_item_id'])
		{
		return true;
		}
	}

function del_item($item_id)
	{
	$ti = array();
	$this->itemqtys[$item_id] = 0;
	foreach($this->items as $item)
		{
		if($item != $item_id)
			{
			$ti[] = $item;
			}
		}
	$this->items = $ti;
	$this->_update_total();
	}

function empty_cart()
	{
	$this->total = 0;
	$this->itemcount = 0;
	$this->items = array();
	$this->itemprices = array();
	$this->itemqtys = array();
	$this->itemname = array();
	}

function _update_total()
	{
	$this->itemcount = 0;
	$this->total = 0;
	if(sizeof($this->items > 0))
		{
		foreach($this->items as $item)
			{
			$this->total = $this->total + ($this->itemprices[$item] * $this->itemqtys[$item]);

			$this->itemcount += $this->itemqtys[$item];
			}
		}
	}

function display_cart($jcart)
	{
	extract($jcart);

	$item_id = $_POST[$item_id];
	$item_qty = $_POST[$item_qty];
	$item_price = $_POST[$item_price];
	$item_name = $_POST[$item_name];

	if ($_POST[$item_add])
		{
		$item_added = $this->add_item($item_id, $item_qty, $item_price, $item_name);

		if ($item_added !== true)
			{
			$error_type = $item_added;
			switch($error_type)
				{
				case 'qty':
					$error_message = $text['quantity_error'];
					break;
				case 'price':
					$error_message = $text['price_error'];
					break;
				}
			}
		}

	if ($_POST['jcart_update_item'] == $jcart['text']['update_button'])
		{
		$item_updated = $this->update_item($_POST['item_id'], $_POST['item_qty']);
		if ($item_updated !== true)
			{
			$error_message = $text['quantity_error'];
			}
		}

	if($_POST['jcart_update_cart'] || $_POST['jcart_checkout'])
		{
		$cart_updated = $this->update_cart();
		if ($cart_updated !== true)
			{
			$error_message = $text['quantity_error'];
			}
		}

	if($_GET['jcart_remove'] && !$_POST[$item_add] && !$_POST['jcart_update_cart'] && !$_POST['jcart_check_out'])
		{
		$this->del_item($_GET['jcart_remove']);
		}

	if($_POST['jcart_empty'])
		{
		$this->empty_cart();
		}

	if ($this->itemcount >= 0)
		{
		$text['items_in_cart'] = $text['multiple_items'];
		}
	if ($this->itemcount == 1)
		{
		$text['items_in_cart'] = $text['single_item'];
		}

	$is_checkout = strpos($_SERVER['REQUEST_URI'], $form_action);
	if ($is_checkout !== false || $_REQUEST['jcart_is_checkout'] == 'true')
		{
		$is_checkout = true;
		}
	else
		{
		$is_checkout = false;
		}

	if ($is_checkout == true)
		{
		$form_action = $path . 'jcart-gateway.php';
		}

	$input_type = 'submit';


	if ($_SESSION['quantity_error'] == true)
		{
		$error_message = $text['quantity_error'];
		unset($_SESSION['quantity_error']);
		}

	if ($error_message)
		{
		$error_message = "<p class='jcart-error'>$error_message</p>";
		}

	echo "<!-- BEGIN JCART -->\n<div id='jcart'>\n";
	echo "\t$error_message\n";
	echo "\t<form method='post' action='$form_action'>\n";
	echo "\t\t<fieldset>\n";
	echo "\t\t\t<table border='1'>\n";
	echo "\t\t\t\t<tr>\n";
	echo "\t\t\t\t\t<th id='jcart-header' colspan='3'>\n";
	echo "\t\t\t\t\t\t<strong id='jcart-title'>" . $text['cart_title'] . "</strong> (" . $this->itemcount . "&nbsp;" . $text['items_in_cart'] .")\n";
	echo "\t\t\t\t\t</th>\n";
	echo "\t\t\t\t</tr>". "\n";


	if($this->itemcount > 0)
		{


		foreach($this->get_contents() as $item)
			{
			echo "\t\t\t\t<tr>\n";

			echo "\t\t\t\t\t<td class='jcart-item-qty'>\n";
			echo "\t\t\t\t\t\t<input type='text' size='2' id='jcart-item-id-" . $item['id'] . "' name='jcart_item_qty[ ]' value='" . $item['qty'] . "' />\n";
			echo "\t\t\t\t\t</td>\n";
			echo "\t\t\t\t\t<td class='jcart-item-name'>\n";
			echo "\t\t\t\t\t\t" . $item['name'] . "<input type='hidden' name='jcart_item_name[ ]' value='" . $item['name'] . "' />\n";
			echo "\t\t\t\t\t\t<input type='hidden' name='jcart_item_id[ ]' value='" . $item['id'] . "' />\n";
			echo "\t\t\t\t\t</td>\n";
			echo "\t\t\t\t\t<td class='jcart-item-price'>\n";
			echo "\t\t\t\t\t\t<span>" . $text['currency_symbol'] . number_format($item['subtotal'],2) . "</span><input type='hidden' name='jcart_item_price[ ]' value='" . $item['price'] . "' />\n";
			echo "\t\t\t\t\t\t<a class='jcart-remove' href='?jcart_remove=" . $item['id'] . "'>" . $text['remove_link'] . "</a>\n";
			echo "\t\t\t\t\t</td>\n";
			echo "\t\t\t\t</tr>\n";
			}
		}


	else
		{
		echo "\t\t\t\t<tr><td colspan='3' class='empty'>" . $text['empty_message'] . "</td></tr>\n";
		}

	echo "\t\t\t\t<tr>\n";
	echo "\t\t\t\t\t<th id='jcart-footer' colspan='3'>\n";

	if ($is_checkout !== true)
		{
		if ($button['checkout']) { $input_type = 'image'; $src = ' src="' . $button['checkout'] . '" alt="' . $text['checkout_button'] . '" title="" ';	}
		echo "\t\t\t\t\t\t<input type='" . $input_type . "' " . $src . "id='jcart-checkout' name='jcart_checkout' class='jcart-button' value='" . $text['checkout_button'] . "' />\n";
		}

	echo "\t\t\t\t\t\t<span id='jcart-subtotal'>" . $text['subtotal'] . ": <strong>" . $text['currency_symbol'] . number_format($this->total,2) . "</strong></span>\n";
	echo "\t\t\t\t\t</th>\n";
	echo "\t\t\t\t</tr>\n";
	echo "\t\t\t</table>\n\n";

	echo "\t\t\t<div class='jcart-hide'>\n";
	if ($button['update']) { $input_type = 'image'; $src = ' src="' . $button['update'] . '" alt="' . $text['update_button'] . '" title="" ';	}
	echo "\t\t\t\t<input type='" . $input_type . "' " . $src ."name='jcart_update_cart' value='" . $text['update_button'] . "' class='jcart-button' />\n";
	if ($button['empty']) { $input_type = 'image'; $src = ' src="' . $button['empty'] . '" alt="' . $text['empty_button'] . '" title="" ';	}
	echo "\t\t\t\t<input type='" . $input_type . "' " . $src ."name='jcart_empty' value='" . $text['empty_button'] . "' class='jcart-button' />\n";
	echo "\t\t\t</div>\n";

	if ($is_checkout == true)
		{

		echo "\t\t\t<input type='hidden' id='jcart-is-checkout' name='jcart_is_checkout' value='true' />\n";

		$protocol = 'http://'; if (!empty($_SERVER['HTTPS'])) { $protocol = 'https://'; }
		echo "\t\t\t<input type='hidden' id='jcart-checkout-page' name='jcart_checkout_page' value='" . $protocol . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI'] . "' />\n";

		if ($button['paypal_checkout'])	{ $input_type = 'image'; $src = ' src="' . $button['paypal_checkout'] . '" alt="' . $text['checkout_paypal_button'] . '" title="" '; }
		echo "\t\t\t<input type='" . $input_type . "' " . $src ."id='jcart-paypal-checkout' name='jcart_paypal_checkout' value='" . $text['checkout_paypal_button'] . "'" . $disable_paypal_checkout . " />\n";
		}
	echo "\t\t</fieldset>\n";
	echo "\t</form>\n";

	if ($_POST['jcart_update_item'])
		{
		echo "\t" . '<script type="text/javascript">$(function(){$("#jcart-item-id-' . $_POST['item_id'] . '").focus()});</script>' . "\n";
		}

	echo "</div>\n<!-- END JCART -->\n";
	}
}
?>

bradgrafelman

willow wrote:
Thought I would post the code that is called in on the store.php page if this will help

It only "helps" in the sense that it confirms what I said above.

For example, this if() statement:

if (is_array($_POST['jcart_item_ids']))

and this one:

 if ($_POST['jcart_item_id'])

both fail to ensure that the external variables being referenced exist before attempting to access them.

willow

Thanks for getting back to me.

This was supplied as is by http://conceptlogic.com/jcart - will try their forum as well.

I undertand what you are saying as a heavy user of actionScript.

Although I am still unsure as to why this would work on a local server but not on a remote one?

Is this a common [consistent] problem?

If it is I'll file for future refrence.

Many thanks,

Regards,

Willow.

bradgrafelman

willow wrote:
Although I am still unsure as to why this would work on a local server but not on a remote one?

The error messages you posted are just notices. Presumably, they will go away when you actually submit the form and the variables exist.

One thing to note is that the array indexes won't have dashes in them; PHP will replace all hyphens with underscores, so if the error message truly does have hyphens in it then that would suggest that the code is looking for the wrong array index. However, your latest code snippet doesn't show any references to the array indexes referenced in the error messages you originally posted.