Ajax not updating the cart - Codeigniter - php

Question

I am using ajax to updat codeigniter cart. My problem is when i add multiple items in the cart & update the quantity of items the quantity does not change. It only works for the last item added.
below is my code
<form id="columnarForm" name="columnarForm" enctype="multipart/form-data" method="post">
<table width="100%" align="center" cellpadding="0" cellspacing="0" class="table-responsive table-bordered table-hover">
<tbody>
<?php foreach($products as $product){ ?>
<tr>
<td align="right" valign="middle">
<input readonly type="text" name="name" value="<?php echo $product['name'] ?>"/>
</td>
<td align="right" valign="middle">
<input readonly type="text" name="price" value="<?php echo $product['price'] ?>"/>
</td>
<td align="right" valign="middle">
<input type="text" name="qty" value="<?php echo $product['qty'] ?>"/>
<input type="button" class="btn btn-primary btn-xs change" value="Change" />
</td>
<input type="hidden" name="rowid" value="<?php echo $product['rowid'] ?>"/>
</tr>
<script type="text/javascript">
$(function(){
$('.change').click(function(){
$.ajax({
type: "POST",
url: "<?php echo base_url()?>update-shopping-cart",
data: $("#columnarForm").serialize(),
beforeSend: function(){
$('#result').html('<img src="<?php echo site_url('assets/images/loading.gif'); ?>" class="center-block" />');
},
success: function(data){
$('#result').html(data);
}
});
});
});
</script>
<? } ?>
</tbody>
</table>
</form>
My Controller
// Updated the shopping cart
function updateCart(){
$data = array(
'rowid' => $this->input->post('rowid'),
'qty' => $this->input->post('qty'),
);
// Update the cart with the new information
$this->cart->update($data);
redirect(base_url().'update-cart-view');
}

Answer 1

You are looping through your products and setting all input names to be the same thing:
<td align="right" valign="middle">
<input readonly type="text" name="name" value="<?php echo $product['name'] ?>"/>
</td>
<td align="right" valign="middle">
<input readonly type="text" name="price" value="<?php echo $product['price'] ?>"/>
</td>
<td align="right" valign="middle">
<input type="text" name="qty" value="<?php echo $product['qty'] ?>"/>
So you end up with x amount of "name"s, x amount of "price"s and x amount of "qty"s. And your code grabs an element "name" with "price" with "qty". On submit, because all the inputs are in the same form, you send ALL of the information, but process only one set.
Either use the 'rowid' with every element name - 'price_rowid', 'name_rowid' and 'qty_rowid' so you can loop through all values, or loop through all post data on submit.