Redirect successfully after loop is completed - php

Question

i have a shopping cart session which completely inserts into the database through a loop, once i make a redirect to the session, it inserts only one product out of the multiple products in the session.
for($i = 0; $i < count($_SESSION['shopping_cart']); $i++){
$title = $_POST['title'][$i];
$quantity = $_POST['quantity'][$i];
$total = $_POST['total'][$i];
$sql = "INSERT INTO orders (title, quantity, total, paid, created_at, updated_at)";
$sql .= " VALUES ( '";
$sql .= $title . "', '";
$sql .= $quantity . "', '";
$sql .= $total . "', '";
$sql .= 0 . "', '";
$sql .= $timestamp . "', '";
$sql .= $timestamp . "')";
$result = $database->query($sql);
if($result){
//success
echo 'yes';
//redirect_to('order_summary.php');
}else{
echo 'no';
//failure
}
}
This is the table below, i am abit confused as to why whenever i make the page redirect, the for loop is not totally inserted in the database, but each time i remove the redirect, it loops completely with all the details into the database.
<table class="table table-striped">
<tr>
<th colspan="7"><h3 class="text-center">Order details</h3></th>
</tr>
<tr class="bg bg-success">
<th>Title</th>
<th>Slug</th>
<th>Description</th>
<th>Price</th>
<th>Quantity</th>
<th>Total</th>
<th>Actions</th>
</tr>
<?php
if(!empty($_SESSION['shopping_cart']));
$total = 0;
foreach($_SESSION['shopping_cart'] as $key => $product):
?>
<form method="post" action="cart5.php" class="form-horizontal">
<tr>
<td class="text-info"><input type="text" readonly class="form-control" name="title[]" value="<?php echo $product['title']; ?>"/></td>
<td><input type="text" readonly class="form-control" name="price[]" value="N<?php echo $product['price']; ?>"/></td>
<td class="text-center text-info"><input type="text" readonly class="form-control" name="quantity[]" value="<?php echo $product['quantity']; ?>"/></td>
<td><input type="text" readonly class="form-control" name="total[]" value="N<?php echo number_format($product['quantity'] * $product['price'], 2); ?>"/></td>
</tr>
<?php
$total = $total + ($product['quantity'] * $product['price']);
endforeach;
?>
<tr>
<td class="bg bg-success" colspan="7" align="center"><b>SubTotal = N</b><input type="text" readonly multiple class="form-control" name="subTotal[]" value="<?php echo number_format($total, 2); ?>"/></td>
</tr>
<tr>
<td colspan="7">
<?php
if (isset($_SESSION['shopping_cart'])):
if (count($_SESSION['shopping_cart']) > 0):
?>
<input type="submit" name="submit" class="btn btn-success text-right" value="Checkout" />
<?php endif; endif; ?>
</td>
</tr>
</table>

Answer 1

The problem is that you redirect in the loop after the first success...
for($i = 0; $i < count($_SESSION['shopping_cart']); $i++){
// ....
if($result){
//success
echo 'yes';
//redirect_to('order_summary.php');
}else{
echo 'no';
//failure
}
}
What you need to do is redirect only either on failure or when the loop has finished...
for($i = 0; $i < count($_SESSION['shopping_cart']); $i++){
// ....
if(!$result){
echo 'no';
//failure
redirect_to('failed.php');
}
}
redirect_to('order_summary.php');
Or use a flag which flags what to do after the loop...
$success = true;
for($i = 0; $i < count($_SESSION['shopping_cart']); $i++){
// ....
if(!$result){
echo 'no';
//failure
$success = false;
}
}
if ( $success ) {
redirect_to('order_summary.php');
}
else {
redirect_to('failed.php');
}
This is based on the assumption that redirect_to() is outputting the header and automatically calling exit which will stop the script.
All these have the possibility that they will leave an order half inserted, depending on how important that is may dictate if you want to wrap it all in a transaction or not.

Answer 2

Your logic is telling it to redirect after any successful insert. Hence, first run through the loop it works and it redirects.
Also, you can't send header()s after starting any output to the client - the echo 'yes' may give you problems. I'd change it to set/track a boolean and after the loop is complete do something.
for($i = 0; $i < count($_SESSION['shopping_cart']); $i++){
$title = $_POST['title'][$i];
$quantity = $_POST['quantity'][$i];
$total = $_POST['total'][$i];
$success=true; // assume it works
$sql = "INSERT INTO orders (title, quantity, total, paid, created_at, updated_at)";
$sql .= " VALUES ( '";
$sql .= $title . "', '";
$sql .= $quantity . "', '";
$sql .= $total . "', '";
$sql .= 0 . "', '";
$sql .= $timestamp . "', '";
$sql .= $timestamp . "')";
$result = $database->query($sql);
if(!$result){
// failure do something like trapping the sql error,
// or recording a message in an array
$success=false;
}
}
if($success){
// it all worked!
// do your redirect here
}else{
// something failed
// do your error output, warning to user, whatever here
}