Using class inside a function

[lazeelaker]

I'm trying to utilize a class from inside a function. I've set an object of the class outside the function and inside the function, when outside did not work. The error for outside the function is "Fatal error: Call to a member function on a non-object in generate.php on line 103". The error for inside the function is: "Fatal error: Call to undefined function: query() in generate.php on line 100". I don't understand what is wrong. Can anyone help?

[devinemke]

code?

[lazeelaker]

Object outside function:
//connect to the database
$db = DB::connect("blah");
function getDents()
{
//dent Query
$getDent = "some query";
$query = $db->query($getDent);
[INDENT]// the above line generates the error message "Fatal error: Call to a member function on a non-object in generate.php on line 103"[/INDENT]
}

Object inside function:
function getDents()
{
//dent Query
$getDent = "some query";
//connect to the database
$db = DB::connect("blah");
$query = $db->query($getDent);
[INDENT]// the above line generates the error message "Fatal error: Call to undefined function: query() in generate.php on line 100"[/INDENT]
}
I've verified that my queries are legitimate.

[lazeelaker]

Just in case this will help
The function call is inside a nested if and the function is supposed to return the retrieved results from the query in an array.
if ($_SESSION['loginTime'] < time())
{
$msg = "Your session has timed out. Please sign on again.";
session_destroy();
include("index.php");
}
else
{
if ($proTypeD == "dents")
{
$medInfo .= getDents();
}
}

[ZibingsCoder]

Might want to read up on variable scope as well. Will explain why it wasn't working outside of the function.

[lazeelaker]

I've read over the variable scope (probably much too fast) and I still do not understand why the function isn't recognized. I know this should be simple, but I just can't seem to get over this road block. Should I have a variable declared global? If so, which one and why?

[ahundiak]

$db = DB::connect("blah");
function getDents()
{
  global $db;
  $getDent = "some query";
  $query = $db->query($getDent);
} 

[Weedpacket]

Because unless you declare them global inside the function, variables defined outside the function aren't available inside the function.

[lazeelaker]

I feel like such an idiot. Everything worked out. Thanks.

[sarahlanghorne]

I am having a similar problem. I don't believe I am using any variables from outside my function though. I receive the error: "Call to a member function query() on a non-object" for the line that contains $result = $conn->query($query);

Here is my function:

function calculate_price ($cart) {
$price = 0.0;
if (is_array($cart)) {
$conn = db_connect();
foreach ($cart as $item_id => $qty) {
$query = "select price from products where item_id='$item_id'";
$result = $conn->query($query);
if ($result) {
$item = $result->fetch_object();
$item_price = $item->price;
$price +=$item_price*$qty;
}
}
}
return $price;
}

I appreciate any help! Thanks!

Sarah

[Weedpacket]

Sounds like $conn is not an object. Is it supposed to be? Have you looked to see what db_connect() is returning?

[sarahlanghorne]

that seems to be the problem but I am new to php... this is what I have for my db_connect() function:

function db_connect() {
$result = @mysql_connect ('localhost', 'user', 'password', 'db_name');
if (!$result)
throw new Exception('Could not connect to database server');
else
return $result;
}

(too bad I can't choose a lightbulb that's not lit for my message icon 😃 😃 😃 )

[ahundiak]

Might want to take a look at mysql_connect (hint: it does not return an object).
http://www.php.net/manual/en/function.mysql-connect.php

And since throwing exceptions implies using PHP 5.x then I'd suggest shifting to PDO which is object based.
http://www.php.net/manual/en/ref.pdo.php