arrays in sessions

watts

I'm working on a lightbox using an array stored in a session and I'm trying to figure out how to empty the lightbox and also how to delete individual items. I have a button at the bottom of the page for clearing the lightbox using this code (sessionDbTest4 is the current file):

echo "<form action='sessionDbTest4.php' method='get'>\n
      <input type='hidden' name='clear' value='true'>\n
      <input type='submit' value='Clear Cart'>\n
      </form>";

and then closer to the top of the page I have the code:

if ($clear=='true')
{
  unset($_SESSION['subcategories']);
}

and instead of emptying the array it displays the whole list of items that were in the array but then at the end it says "could not execute query" which is the or die message for the display loop query. Any suggestions on how I should be doing this?

devinemke

you don't need the hidden form field

<?php
session_start();
if (isset($_POST['submit']) && $_POST['submit'] == 'Clear Cart') {unset($_SESSION['subcategories']);}
?>

<form action="" method="POST">
<input type="submit" name="submit" value="Clear Cart">
</form>

watts

I just tried this but it didn't fix the problem. It's still not clearing the lightbox for some reason unset isn't unsetting.

devinemke

how exactly have you implemented my suggested code?

watts

As far as I can tell, exactly as intended:

if (isset($_GET['submit']) && $_GET['submit'] == 'Clear Cart') {unset($_SESSION['subcategories']);}

echo "<form action='sessionDbTest4.php' method='get'>\n

  <input type='submit' value='Clear Cart'>\n
  </form>";

but when I click on clear cart it displays all the items that were in the cart followed by the die message (could not execute query) that I set in the display loop. So the cart is being cleared but something has happened in the session because until I completely close the browser and then reload the file I still get the die message.

devinemke

post the code

watts

<?php

  session_start();

if (isset($_GET['submit']) && $_GET['submit'] == 'Clear Cart') {unset($_SESSION['subcategories']);}

include ("connect.inc");

?>
<html>
<head><title>Testing Sessions page 2</title></head>
<body>
<?php

if (isset($_SESSION['subcategories'])) 
{

$_SESSION['subcategories'][]=$subID;
echo "array was not empty<br>";

foreach ($_SESSION['subcategories'] as $key => $subCat)
  {
  $query = "SELECT * FROM subcategories WHERE subID=$subCat";
  $result = mysql_query($query)
	or die ("couldn't execute query");
  $row = mysql_fetch_array($result,MYSQL_ASSOC);
  extract($row);  

  echo "subcategory $key = $subName<br>\n";
  echo "why always $subCat?<hr>";

  }

} else {

$_SESSION['subcategories'][]=$subID;
echo "array was empty<br>";
foreach ($_SESSION['subcategories'] as $key => $subCat)
  {
  $query = "SELECT * FROM subcategories WHERE subID=$subCat";
  $result = mysql_query($query)
or die ("couldn't execute query");
  $row = mysql_fetch_array($result,MYSQL_ASSOC);
  extract($row);  
  echo "subcategory $key = $subName<br>\n";
  }

}

echo "<a href='sessionDbTest3.php'>Back</a>\n";
echo "<form action='sessionDbTest4.php' method='get'>\n

  <input type='submit' value='Clear Cart'>\n
  </form>";

?>
</body>
</html>

devinemke

you are never setting the $subID variable, unless it's being set somewhere inside of "connect.inc" or you have register_globals turned on and it is a form submitted variable.

watts

I just fixed that by setting at the top of the file but it didn't fix anything. Now it's running the code for if the session variable is set but it's unable to execute the query, it seems to be getting worse not better.

devinemke

debugging basics:

simpilfy the code to isolate the problem
use [man]print_r[/man] to inspect the contents of arrays
echo queries before running to make sure they are valid
use [man]mysql_error[/man] to see what mySQL thinks is the problem

bombytza

Maybe you should enclose the value of the variable in the mysql query in simple qoutes

$query = "SELECT * FROM subcategories WHERE subID=[B]'[/B]$subCat[B]'[/B] ";

Like devinemke said, you should use

or die (mysql_error());

after mysql queries when you are debugging (not in live sites because of possible security matters).