How to add +1 to var with href? - php

Question

I have this quantity (var name: $Quantidade) displayed from a cart and need to add + and - hrefs to make it increase/decrease value.
Quantity:
quantity
Full table:
table
The quantity var always starts at 1.
All my attempts have failed.
Here is some code for the table (works if the + href is removed):
<table class="cart" width=700px cellpadding="0" cellspacing="0" style="border: 1px;" rules="none" align="center">
<tr height=40px align="center">
<td>Product</td>
<td>Price</td>
<td></td>
<td>Quantity</td>
<td></td>
<td>Delete</td>
</tr>
<?php
// Carrinho
$total=0;
foreach($_SESSION['venda'] as $Prod => $Quantidade):
$SqlCarrinho = mysqli_query($conect,"SELECT * FROM produto WHERE id= '$Prod'");
$ResAssoc = mysqli_fetch_assoc($SqlCarrinho);
echo '<tr height=40px align="center">';
echo '<td>'.$ResAssoc['descricao'].'</td>';
echo '<td>'.number_format($ResAssoc['preco'],2,",",".").'€</td>';
echo '<td>-</td>';
echo '<td>'.$Quantidade.'</td>';
echo '<td>+</td>';
echo '<td>x</td>';
$total += $ResAssoc['preco'] * $Quantidade;
echo '</tr>';
endforeach;
echo '<tr height=40px>';
echo '<td colspan="6" align="right">Total: '.number_format($total,2,",",".").'€</td>';
echo '</tr>';
echo'</table>';
Here is some code for the sessions I use:
session_start();
if(isset($_POST['more'])){ $_SESSION['venda'] [$_GET['par']] = $_GET['par'] + 1 ; }
if(isset($_SESSION['venda'])){}
else{ $_SESSION['venda'] = array(); }
if(isset($_GET['par'])){ $_SESSION['venda'] [$_GET['par']] = 1 ; }
if(isset($_GET['del'])){
$Del = $_GET['del'];
unset($_SESSION['venda'][$Del]);
Everything works until I add the + href, then it disformats the table:
broken table
I have confirmed its not a css error, the href is gone with/without css.

Answer 1

You need to remove the # in the link.
<a href="?more=true&par='.$Prod.'>+</a>
instead of
<a href="#?more=true&par='.$Prod.'>+</a>
When sending requests to your server, the browser ignores everything after the first #. Your GET parameters are not sent with the request currently.
Update
Check out the marked line. It resets venda → par every time par is set (which is always the case if you want to increase your value). Maybe you also want this to initialize the var. In this case you need to fix the if statement (if(!isset($_GET['par'])){ /* ... */ }). Venda gets reseted too.
session_start();
if(isset($_POST['more'])){ $_SESSION['venda'] [$_GET['par']] = $_GET['par'] + 1 ; }
if(isset($_SESSION['venda'])){}
else{ $_SESSION['venda'] = array(); }
// This line
if(isset($_GET['par'])){ $_SESSION['venda'] [$_GET['par']] = 1 ; }
if(isset($_GET['del'])){
$Del = $_GET['del'];
unset($_SESSION['venda'][$Del]);
Update 2
I think you want the code like this:
session_start();
// First, check if all vars are initialized
// Init if 'venda' is NOT set
if (!isset($_SESSION['venda'])) {
$_SESSION['venda'] = array();
}
// Init if 'venda['par'] is not set
if (isset($_GET['par']) && !isset($_SESSION['venda'][$_GET['par']])) {
$_SESSION['venda'][$_GET['par']] = 1;
}
// Run the updates/deletions
// Increase if 'more' is set
if (isset($_POST['more']) && isset($_GET['par'])) {
$_SESSION['venda'][$_GET['par']] += 1;
}
// Delete
if (isset($_GET['del'])) {
$Del = $_GET['del'];
unset($_SESSION['venda'][$Del]);
}