I'm getting a 'Call to a member function on a non-object' error on line 25. ( I have commented line 25 for you). Any ideas what the problem might be?

PHP Code:

class categorygenerator {
   var $root_uniqueid = 0,
       $max_level = 6,
       $data = array(),
       $root_start_string = '',
       $root_end_string = '',
       $parent_start_string = '',
       $parent_end_string = '',
       $parent_group_start_string = '<ul%s>',
       $parent_group_end_string = "</ul>\n",
       $child_start_string = '<li%s>',
       $child_end_string = "</li>\n",
       $spacer_string = '',
       $spacer_multiplier = 1;
  function categorygenerator($load_from_database = true) {
     global $db;
  $this->data = array();
  $categories_query = "SELECT pagetitle, uniqueid, parentid FROM category WHERE uniqueid = 'uniqueid' ORDER BY parentid, pagetitle";
        $categories = $db->Execute($categories_query); // line 25
         while (!$categories->EOF) {
           $this->data[$categories->fields['parentid']][$categories->fields['uniqueid']] = array('name' => $categories->fields['pagetitle'], 'count' => 0);
        $categories->MoveNext();
         }
  } 


It means $db is not an object.

I see that you have global $db; you may want to check where you are instantiating it at.

Yup.. What did you do with $db in your other files? Another thing to try is make sure your "execute" function isn't capitalized wherever you initialized it. I've only had this error once so I'm not sure if that'd be it but I really don't think so. Still something to try.

I think this code is modified from something like Zen Cart or OSC, if memory serves. It'd really depend on when the function is called. I'd say to go back and check the calling script and go from there. Also, the function declaration has a parameter that is never used, so why include it?

1) You dont include a file with db class
2) You type wrong the method name 'Excecute'
3) The db class not create the cnnection or something wrong more on top of the code. Set error_reporting(E_ALL) prior file of db class to view if there is previous errors.