Add input form inside a table - php

Question

So inside my table before tbody tag, I inserted a form inside tbody. However while submitting its form, the url is getting btnchange.php?qty=1 instead of btnchange.php?prod_id=cartno.
shopcart.php
<?php // start
$stmt = $DB_con->prepare("SELECT * FROM cart WHERE cartuser = '$userid' and cartpend='IN CART'");
$stmt->execute();
if($stmt->rowCount() > 0)
{
while($row=$stmt->fetch(PDO::FETCH_ASSOC))
{
extract($row); //end ?>
<form method="get" action="btnchange.php?prod_id=<?php echo $row['cartno'] ?>">
<tbody>
<tr>
<td><?php echo $row['cartno']; ?></td>
<td><?php echo $row['cartname']; ?></td>
<td><?php echo $row['cartprice']; ?></td>
<td><input type="text" name="qty" value="<?php echo $row['cartqty']; ?>"></td>
<td><?php echo $row['cartsub']; ?></td>
<td><span class="label label-primary"><?php echo $row['cartpend']; ?></span></td>
<td><button type="submit" name="submit">Submit Quantity</button></b>
<td><a class="btn btn-danger btn-xs" href="?delete_id=<?php echo $row['cartno']; ?>" title="click for delete" onclick="return confirm('Sure to Delete?')"><i class="fa fa-trash-o"></i> Remove</a></td>
</tr>
</tbody>
</form>
This is my btnchange.php code, this is what i used to get the prod_id code and the qty input from shopcart.php.
btnchange.php
//get prod id
if(isset($_GET['prod_id']) && !empty($_GET['prod_id']))
{
$prod_code = $_GET['prod_id'];
$newqty = $_GET['qty'];

Answer 1

You can't put query parameters in the action attribute. You need to use a hidden input instead:
<?php // start
$stmt = $DB_con->prepare("SELECT * FROM cart WHERE cartuser = '$userid' and cartpend='IN CART'");
$stmt->execute();
if($stmt->rowCount() > 0)
{
while($row=$stmt->fetch(PDO::FETCH_ASSOC))
{
extract($row); //end ?>
<form method="get" action="btnchange.php">
<input type="hidden" name="prod_id" value="<?php echo $row['cartno']; ?>">
<tbody>
<tr>
<td><?php echo $row['cartno']; ?></td>
<td><?php echo $row['cartname']; ?></td>
<td><?php echo $row['cartprice']; ?></td>
<td><input type="text" name="qty" value="<?php echo $row['cartqty']; ?>"></td>
<td><?php echo $row['cartsub']; ?></td>
<td><span class="label label-primary"><?php echo $row['cartpend']; ?></span></td>
<td><button type="submit" name="submit">Submit Quantity</button></b>
<td><a class="btn btn-danger btn-xs" href="?delete_id=<?php echo $row['cartno']; ?>" title="click for delete" onclick="return confirm('Sure to Delete?')"><i class="fa fa-trash-o"></i> Remove</a></td>
</tr>
</tbody>
</form>