empty cart function

php_krammer

hi guys ive been stuck this this for a while..

now i have this

<?php echo "cartid is $cartId"; ?>

at the bottom of my webpage and this gives me a # that is the number i need to delete out of the cart table.

this code does nothing when i click the button. and im not sure why. can anyone see anything wrong with it?

the remove item function works sweet.

thanx in advance!

Chris

<?php

function GetCartId() 
{ 
// This function will generate an encrypted string and 
// will set it as a cookie using set_cookie. This will 
// also be used as the cookieId field in the cart table 
if(isset($_COOKIE["cartId"])) 
{ 
return $_COOKIE["cartId"]; 
} 
else 
{ 
// There is no cookie set. We will set the cookie 
// and return the value of the users session ID 
setcookie("cartId", session_id(), time() + ((3600 * 24) * 30)); 
return session_id(); 
} 
} 

   switch($_GET["action"]) 
   { 
      case "add_item": 
      { 
         AddItem($_GET["id"], $_GET["qty"]); 
         ShowCart($rs_cart); 
         break; 
      } 
      case "update_item": 
      { 
         UpdateItem($_GET["id"], $_GET["qty"]); 
         ShowCart($rs_cart); 
         break; 
      } 
      case "remove_item": 
      { 
         RemoveItem($_GET["id"]);     

         ShowCart($rs_cart); 
         break; 
      } 
	  case "empty_cart": 
      { 
         EmptyCart($_GET["id"]);     

         ShowCart($rs_cart); 
         break; 
      } 
      default: 
      { 
         ShowCart($rs_cart); 
      } 
   } 
?>

<?php

function RemoveItem($itemId) 
   { 
      // Uses an SQL delete statement to remove an item from 
      // the users cart 

  mysql_query("DELETE FROM cart WHERE cookieId = '" . GetCartId() . "' AND itemId = $itemId"); 
   } 

function EmptyCart($itemId) 
{       

      $query="DELETE * FROM cart WHERE cookieId = $cartId";
	  echo "query is $query<br />"; 
	  mysql_query($query); 

}
?>

<html>
<form name="cart" action=""> 
<input type="submit" value="Reset"  onclick="form.action='cart.php?action=empty_cart'" class="button" /> 
<input type="submit" value="Continue" onclick="form.action='details.php'" class="button" /> 
</form>
</html>

PHPMagician

You call emtpy_cart like this:

RemoveItem($_GET["id"]);

Yet, no variable id is passed via GET when you press the submit button designated to this action.

Also, this script from a glance seems very insecure, no checks on SQL Injection of if the cart belongs to the user, etc. With a shopping cart, these are the concerns you do not want (for obvious reasons).

php_krammer

thanx for your reply PHPMagician,

do you mean

 <?php EmptyCart($_GET["id"]); ?>

instead of?

 <?php RemoveItem($_GET["id"]);  ?>

how can i get my emptycart to work and help?

also, can you please explain some more on what you mean by the cart is insecure?

thanx very much, help much appreciated!

PHPMagician

What I mean is that a parameter 'id' is never passed to the script. When you click remove item or empty basket, you are only sending the parameter 'action' in. So, basically, RemoveItem($_GET['id']) is equivalent to RemoveItem(NULL); cause no 'id' is passed in the query string.

For the security issues I was refering to in particular, look at: http://www.php.net/manual/en/security.database.sql-injection.php