Problem with negative values

[phpphpphp]

Hello, I installed oscommerce and filled it with cellular phones, but sometimes I get a negative price.

I never want a negative price to be shown to the customer. When negative it needs to be 0.

 

I've tried some things like this:

 

includes\class\shopping_cart.php:

 

$zoekterm = "-";

$products_price = $products['products_price'];

$products_price = str_replace($zoekterm, "", $products_price);

 

Or:

\shopping_cart.php:

<?php

$findme = '-';

$pos = strpos($cart->show_total(), $findme);

 

if ($pos === false) {

echo "The string '$findme' was not found in the string '$cart->show_total'";

} else {

$cart = str_replace ( chr ( 45 ), '', $cart );

}

?>

 

Or:

$products_price = str_replace ( chr ( 45 ), "", $products_price);

 

 

Nothing works, please help!