If statement Help

[Struggling]

I am trying to make a script so that if a product already exits in a shopping cart instead of adding it again so it appears twice it updates the current product in the shopping cart with the new quantity.

I have this bit working the problem lies with the fact that the else part of the statement isn't working, so if the product doesn't exist in the cart it won't add it.

Any help appreciated

<?php
session_id();
session_start();
include("database/database.php");
$qty = $_POST['qty'];
$prodnum = $_POST['prodnum'];
$sess = session_id();

if (empty($qty) || !is_numeric($qty))
{include("error.php");
}

$query = "SELECT * from carttemp WHERE sess = '$sess'";
$results = mysql_query($query) or die(mysql_error());
$numrows = mysql_num_rows($results);

	if ($numrows == 1)
	{while ($row = mysql_fetch_array($results)) {
	$prodnumexists = $row[prodnum];
	$currentquan = $row[quan];
		if ($prodnumexists == $prodnum)
		{$updateqty = $currentquan + $qty;
		mysql_query("UPDATE carttemp SET quan = '$updateqty' WHERE prodnum = '$prodnum'");
		}}}
else {
$query1 = "INSERT INTO carttemp (sess, quan, prodnum) VALUES ('$sess','$qty','$prodnum')";
$results1 = mysql_query($query1) or die(mysql_error());
}
include ("cart.php");
exit;
?>

[guido2004]

I changed the indentation of your 'if':

  if ($numrows == 1) {
    while ($row = mysql_fetch_array($results)) {
      $prodnumexists = $row[prodnum];
      $currentquan = $row[quan];
      if ($prodnumexists == $prodnum) {
        $updateqty = $currentquan + $qty;
        mysql_query("UPDATE carttemp SET quan = '$updateqty' WHERE prodnum = '$prodnum'");
      }
    }
  }
  else 
  {
    $query1 = "INSERT INTO carttemp (sess, quan, prodnum) VALUES ('$sess','$qty','$prodnum')";
    $results1 = mysql_query($query1) or die(mysql_error());
  } 

As you can see, if the number of lines found is equal to 1, it'll enter the 'if', else it'll enter the 'else'.

So:
- when you have nothing in your cart, it'll add the new product
- after that, you have 1 product, and it'll enter the 'if'

In the 'if':
- if the product already exists, it'll change the quantity
- else it does nothing

So your second product will never be inserted.

[Struggling]

Sorry that didn't solve the problem.

it will update the current products quantity if the product already exits.

the problem seems to be that as soon as there is one item in the cart it will do nothing else except update so I can't even add another new product.

Cheers

[guido2004]

But I didn't solve your problem. I only told you why it isn't working as you expected.

I think you should change the logic in the script a bit, and make a select based on the session id AND the product code (and the update as well):

<?php
  session_id();
  session_start();
  include("database/database.php");
  $qty = $_POST['qty'];
  $prodnum = mysql_real_escape_string($_POST['prodnum']);
  $sess = session_id();

  if (empty($qty) || !is_numeric($qty)) {
    include("error.php");
  }

  $query = "SELECT * from carttemp WHERE sess = '$sess' AND prodnum = '$prodnum'";
  $results = mysql_query($query) or die(mysql_error());
  
  if (mysql_num_rows($results) == 1) { 
    $row = mysql_fetch_array($results);
    $prodnumexists = $row['prodnum'];
    $currentquan = $row['quan'];
    $updateqty = $currentquan + $qty;
    mysql_query("UPDATE carttemp SET quan = '$updateqty' WHERE sess = '$sess' AND prodnum = '$prodnum'");
  }
  else {
    $query1 = "INSERT INTO carttemp (sess, quan, prodnum) VALUES ('$sess','$qty','$prodnum')";
    $results1 = mysql_query($query1) or die(mysql_error());
  }
  include ("cart.php");
  exit;
?>

[Struggling]

cheers thats spot on, thank you