Auto-Increment Form Input Names With $_SESSION - php

Question

I want to use PHP $_SESSION to access user form-inputted data. The flow looks like this:
STEP 1
User fills out form.
<form method="post" action="review.php">
<input type="text" name="length">
<input type="text" name="width">
<input typ="text" name="quantity">
<input type="submit" value="submit">
</form>
STEP 2
Form data is submitted and 'review.php' converts from POST to SESSION. User reviews form details and adds item to cart.
STEP 3
Item is added to PayPal Shopping Cart. User decides he wants to add another item so user clicks on "continue shopping" and returns to STEP 1.
STEP 1
User fills out form details. Except this time, I want the input name to auto-increment.
For example:
<input type="text" name="length2">
<input type="text" name="width2">
<input type="text" name="quantity2">
And I want it to auto increment however many number of times the user adds new items to the cart.
<input type="text" name="length3">
<input type="text" name="length4">
<input type="text" name="etc">
Usual flow continues... STEP 2 ---> STEP 3
After successful payment in STEP 3, user will be redirected to a new page.
STEP 4(newPage)
All of the purchased items' details will be displayed on this page in order and with the same group. For example, (length, width, quantity) then (length2, width2, quantity2) and so on and so forth. They will each be displayed in different forms.
Those forms will also include <input type="file"> so that the user can upload a file for each form. Each form represents a purchased item.
Once the user uploads files to each corresponding form, they will be submitted to a database.
QUESTION
How can I make the input names auto increment preferably with PHP,
and of course whilst using $_SESSION? I would like the name to
return to its original name after the user's session. So let's say
that same user wanted to order the next day and he ordered 5 items,
the input names would span to 5 (length, length2,..., length5).
How can I display all of the user inputted data in each respective
form(see STEP 4)?
I know I have to do all of the back-end stuff on PHP($_SESSION, forms, etc) but if someone has a jQuery solution for the auto increment and showing all of the data in the end I'm all for it.
Here's What I Was Working With
Tried to use this to display the data with the incremented names but couldn't figure out a solution.
<?php
session_start();
?>
<form>
<?php
$size = $_SESSION['size'];
$variables = array("$size");
$i = 1;
foreach ($variables as $var ) {
$name = "txt".$i;
echo "<input type='text' name='".$name."' value='".$var."' />";
$i++;
}
?>
</form>
Some of you might bring up PayPal IPN. I created an IPN listener as well but it doesn't get called via sandbox. A user on here posted that his IPN listener didn't work on sandbox either but when he went live via paypal.com it did work. Could be the case with mine too, but I want to go ahead and start selling so I need a different approach. Even if my IPN listener does work via paypal.com, I can't risk going live with it without being 100% sure. So if I can use this method for now until I can confirm that my listener works I will do it.
As always I am very grateful for your guys' help.

Answer 1

I actually figured this out a while back. Here's the code I am using:
<?php
if(isset($_POST['submit'])){
$_SESSION['invoice'] = $_POST['invoice'];
$invoice_no = $_SESSION['invoice'];
$decal = array(
'length' => $_POST['os0'],
'width' => $_POST['os1'],
'color' => $_POST['os2'],
'quantity' => $_POST['os3'],
'price' => $_POST['price'],
'submit' => $_POST['submit']
);
$_SESSION['order'][] = $decal;
$i = 0;
}
if(isset($_SESSION['order'])){
foreach($_SESSION['order'] as $sav) {
$i++;
?>
<input type="hidden" name="on0_<?php echo $i; ?>" value="Length">
<div class="decalName">
<label>Custom Decal <?php echo $i; ?></label>
</div>
<div class="label-input">
<label>Length</label><input type="text" name="os0_<?php echo $i; ?>" id="length" size="2" class="num" value="<?php echo $sav['length']; ?>" readonly>
</div>
<input type="hidden" name="on1_<?php echo $i; ?>" value="Width">
<div class="label-input"><label>Width</label><input type="text" name="os1_<?php echo $i; ?>" id="width" size="2" class="num" value="<?php echo $sav['width']; ?>" readonly>
</div>
<input type="hidden" name="on2_<?php echo $i; ?>" value="Color">
<div class="label-input">
<label>Color</label><input type="text" name="os2_<?php echo $i; ?>" value="<?php echo $sav['color']; ?>" readonly>
</div>
<div class="label-input">
<label>Quantity</label><input type="text" name="os3_<?php echo $i; ?>" size="2" class="num" id="quantity" value="<?php echo $sav['quantity']; ?>" readonly>
</div>
<input type="hidden" name="on3_<?php echo $i; ?>" value="quantity">
<input type="hidden" class="num" value="0.20">
<div class="label-input">
<label>Price $:</label><input type="text" class="tot" name="price" value="<?php echo $sav['price']; ?>" readonly>
</div><!--end label-input-->
<?php
}
?>