[SOLVED] call to function on a non object

[aebstract]

I'm getting two errors, but the second one is what has me worried as I have never had this sort of error and don't know what could be causing it. I'm using a bunch of code to get me started on a cart, which is:

 

<?php



/**
* MySQL Database Connection Class
* @access public
* @package SPLIB
*/
class MySQL {
    /**
    * MySQL server hostname
    * @access private
    * @var string
    */
    var $host;

    /**
    * MySQL username
    * @access private
    * @var string
    */
    var $dbUser;

    /**
    * MySQL user's password
    * @access private
    * @var string
    */
    var $dbPass;

    /**
    * Name of database to use
    * @access private
    * @var string
    */
    var $dbName;

    /**
    * MySQL Resource link identifier stored here
    * @access private
    * @var string
    */
    var $dbConn;

    /**
    * Stores error messages for connection errors
    * @access private
    * @var string
    */
    var $connectError;

    /**
    * MySQL constructor
    * @param string host (MySQL server hostname)
    * @param string dbUser (MySQL User Name)
    * @param string dbPass (MySQL User Password)
    * @param string dbName (Database to select)
    * @access public
    */
    function MySQL ($host,$dbUser,$dbPass,$dbName) {
        $this->host=$host;
        $this->dbUser=$dbUser;
        $this->dbPass=$dbPass;
        $this->dbName=$dbName;
        $this->connectToDb();
    }

    /**
    * Establishes connection to MySQL and selects a database
    * @return void
    * @access private
    */
    function connectToDb () {
        // Make connection to MySQL server
        if (!$this->dbConn = @mysql_connect($this->host,
                                      $this->dbUser,
                                      $this->dbPass)) {
            trigger_error('Could not connect to server');
            $this->connectError=true;
        // Select database
        } else if ( !@mysql_select_db($this->dbName,$this->dbConn) ) {
            trigger_error('Could not select database');
            $this->connectError=true;
        }
    }

    /**
    * Checks for MySQL errors
    * @return boolean
    * @access public
    */
    function isError () {
        if ( $this->connectError )
            return true;
        $error=mysql_error ($this->dbConn);
        if ( empty ($error) )
            return false;
        else
            return true;
    }

    /**
    * Returns an instance of MySQLResult to fetch rows with
    * @param $sql string the database query to run
    * @return MySQLResult
    * @access public
    */
    function query($sql) {
        if (!$queryResource=mysql_query($sql,$this->dbConn))
            trigger_error ('Query failed: '.mysql_error($this->dbConn).
                           ' SQL: '.$sql);
        return new MySQLResult($this,$queryResource);
    }
}

/**
* MySQLResult Data Fetching Class
* @access public
* @package SPLIB
*/
class MySQLResult {
    /**
    * Instance of MySQL providing database connection
    * @access private
    * @var MySQL
    */
    var $mysql;

    /**
    * Query resource
    * @access private
    * @var resource
    */
    var $query;

    /**
    * MySQLResult constructor
    * @param object mysql   (instance of MySQL class)
    * @param resource query (MySQL query resource)
    * @access public
    */
    function MySQLResult(& $mysql,$query) {
        $this->mysql=& $mysql;
        $this->query=$query;
    }

    /**
    * Fetches a row from the result
    * @return array
    * @access public
    */
    function fetch () {
        if ( $row=mysql_fetch_array($this->query,MYSQL_ASSOC) ) {
            return $row;
        } else if ( $this->size() > 0 ) {
            mysql_data_seek($this->query,0);
            return false;
        } else {
            return false;
        }
    }

    /**
    * Returns the number of rows selected
    * @return int
    * @access public
    */
    function size () {
        return mysql_num_rows($this->query);
    }

    /**
    * Returns the ID of the last row inserted
    * @return int
    * @access public
    */
    function insertID () {
        return mysql_insert_id($this->mysql->dbConn);
    }

    /**
    * Checks for MySQL errors
    * @return boolean
    * @access public
    */
    function isError () {
        return $this->mysql->isError();
    }
}


function checkNum($checknum){
  return ($checknum%2) ? TRUE : FALSE;
}


$host = 'localhost';
$user = 'berryequipment';
$pass = 'gU8Kso8Y';
$name = 'berryequipment_net_db';
$db = &new MySQL($host,$user,$pass,$name);


function writeShoppingCart() {
$cart = $_SESSION['cart'];
if (!$cart) {
return '(0)';
} else {
// Parse the cart session variable
$items = explode(',',$cart);
$s = (count($items) > 1) ? 's':'';
return '(<a href="cart.php">'.count($items).'</a>)';
}
}



function showCart() {
$cart = $_SESSION['cart'];
if ($cart) {
	$items = explode(',',$cart);
	$contents = array();
	foreach ($items as $item) {
		$contents[$item] = (isset($contents[$item])) ? $contents[$item] + 1 : 1;
	}
	$output[] = '<form action="index.php?page=cart&action=update" method="post" id="cart">';
	$output[] = '<table>';
	foreach ($contents as $id=>$qty) {
		$sql = 'SELECT * FROM p_products WHERE id = '.$id;
		$result = $db->query($sql);
		$row = $result->fetch();
		extract($row);
		$output[] = '<tr>';
		$output[] = '<td><a href="index.php?page=cart&action=delete&id='.$id.'" class="r">Remove</a></td>';
		$output[] = '<td>'.$title.' by '.$author.'</td>';
		$output[] = '<td>£'.$price.'</td>';
		$output[] = '<td><input type="text" name="qty'.$id.'" value="'.$qty.'" size="3" maxlength="3" /></td>';
		$output[] = '<td>£'.($price * $qty).'</td>';
		$total += $price * $qty;
		$output[] = '</tr>';
	}
	$output[] = '</table>';
	$output[] = '<p>Grand total: £'.$total.'</p>';
	$output[] = '<div><button type="submit">Update cart</button></div>';
	$output[] = '</form>';
} else {
	$output[] = '<p>You shopping cart is empty.</p>';
}
return join('',$output);
}



?>

 

My errors are:

 

Notice: Undefined variable: db in /home/virtual/site21/fst/var/www/html/performance/functions.php on line 232

 

Fatal error: Call to a member function query() on a non-object in /home/virtual/site21/fst/var/www/html/performance/functions.php on line 232

[Zhadus]

If you have an undefined variable, and a function is using it, it's a non-object. That would be the first thing to investigate.

[aebstract]

$db = &new MySQL($host,$user,$pass,$name);

Well there is this, is there a reason for &new? possibly what is throwing it off? If not.. the variable should be defined.

[printf]

$db in the function showCart() is not defined, either declare global in that function or pass it to that function!

[aebstract]

I've never been one to do functions and am just starting to use them, how do I declare that variable in the function or globally for that matter?

[phparray]

This is the line causing the error.

 

 

$result = $db->query($sql);

 

$db is not defined is causing the second error Call to a member function query()

 

That means for some $db = &new MySQL($host,$user,$pass,$name); is not being processed before $result = $db->query($sql);

 

just make sure your call to showCart() happens after including this function file and I believe it will be ok.

 

Something like this.

 

require_once('performance/functions.php');
showCart();

 

[aebstract]

Here's the problem with that. I have it included at the very top of my index.php file, before anything else happens. Not only that, I removed it from there and tryed it just like you showed on my cart.php and I am still getting the error. Is something out of order in the actual functions.php?

[printf]

Wherever you call show showCart();, change it to...

 

// method #1

 

showCart ( $db );

 

 

or declare global in the function...

 

 

// method #2

 

function showCart() {

   global $db;
   $cart = $_SESSION['cart'];
   if ($cart) {

//...

 

then call it as before (for method #2)

 

showCart ();

 

 

 

 

[aebstract]

Sweet I got those initial errors gone, a few left that I can work out but the main portion of this is working. Just need to do some tweaking to fix it up. Thanks

(went with the global, btw)