Fatal error: Call to a member function on a non-object in /home2/racingri/public_html

[Matt_T]

I never recieved this error before, but have it now.

Not sure what the problem is, here is the show_ads.php code:

<?php
require('header.php');

//If $_GET['cat'] isn't set...
if(!isset($_GET['cat']) || $_GET['cat'] == '')
	echo 'No ads in this category. Please try again.'; //Print the error and stop.

//Otherwise...
else
{
	//Grab all the ads in the category, and show 'em. Order them by views if $_GET['Hot'] == 'true'; else, order them by date
	$sql->query("SELECT * FROM ads WHERE category = '%s' ORDER BY ".(($_GET['Hot'] == 'true') ? "views" : "date")." DESC", $_GET['cat']);
	if($sql->num_rows() == 0)
		echo 'Sorry. There are no ads in this category. Please try again later.';

foreach($sql->getrowset() as $ad)
{
	$ad2 = new CAd($sql);
	$ad2->LoadAd($ad['ID']);
	echo $ad2->OutputAd();
}
}
require('footer.php');
?>

Can anyone help me here?

Thanks. 🙂

[HP400]

looks like there is an error in either your $sql or $ad2 object. What line is it?

[Matt_T]

Line 12, sorry.

Line 12 -
$sql->query("SELECT * FROM ads WHERE category = '%s' ORDER BY ".(($GET['Hot'] == 'true') ? "views" : "date")." DESC", $GET['cat']);

[Kudose]

Looks like you never created the object to work with, unless it was done in your include file.

i.e.

$sql = new SQL;

The error is basically saying that you cannot use functions from an object that doesn't exist.

[Matt_T]

So I should put:

$sql = new SQL;

Above line 12? (Perhaps Line 11?)

Thanks for the reply! 🙂

[Kudose]

Well, it depends on the name of your class. If you class that holds the sql member functions is called SQL, then yes. Otherwise, if your class is called MySQLClass, then you would need:

$sql = new MySQLClass;

And line 11 is fine.

[Matt_T]

Getting closer! Thanks! 🙂

I got an error because it's not the right class:

Fatal error: Cannot instantiate non-existent class: sqlclass in /home2/racingri/public_html/show_ads.php on line 12

Where would I find out what the right class is?

Thanks 🙂

[Kudose]

Look around your files, generally people use a naming convention ... like class.db.cin.php or dbClass.inc.php or class_DB.inc.php or something.

Maybe it is in a shared functions file, or shared classes file.

i.e. functions.php or classes.php

Other than that, I dont really know how to find it.

[Houdini]

Don't use classes if you don't know where they are just send a normal query

$sql =("SELECT * FROM ads WHERE category = '%s' ORDER BY ".(($_GET['Hot'] == 'true') ? "views" : "date")." DESC", $_GET['cat']);

instead of

$sql->query("SELECT * FROM ads WHERE category = '%s' ORDER BY ".(($_GET['Hot'] == 'true') ? "views" : "date")." DESC", $_GET['cat']);

and so on, otherwise without including that class and creating a new instance of it you won't have anything but trouble.

[Kudose]

But what if the class provides SQL injection prevention?

[samudasu]

Even when you do figure out where the class is it won't work because your query isn't valid.

[bradgrafelman]

Kudose wrote:

But what if the class provides SQL injection prevention?

Then it's unnecessary, because [man]mysql_real_escape_string/man along with a little intuition does the same thing. Besides, I would think it's better for a programmer to know how to prevent SQL injection, rather than just rely on a class to do all of that for him.

[Kudose]

Yes, but do we know that this programmer is capable to do so and isn't relying on the class to do so for him/her?

😉

[bradgrafelman]

No we don't. All the more reason to ditch the class and learn how to use the different functions 🙂

[Kudose]

Touche 🙂