Re: Warning: Division by zero

> I have a script that is a result of data entered in a form > On the script (when I test without data entry), I am getting a warning that > Warning: Division by zero in .inc.php on line 15. > The warning is correct, however the viewer cannot access the second script > without entering the data that would cancel the warning. > Is this something I should worry about? or would it be better to right in an > isset? Well, just as a general rule, you'll want to validate all possible user input. That includes checking whether or not particular input has been defined, whether or not it is valid for it's intended use and whether or not it's malicious. Applying that guideline to your situation, I would check to see if: * the input is set * the input is numeric If either or those are not true, I would default the value to 1 since division is being used. e.g., $iVar = 1; if(( isset( $_REQUEST['MY_NUMBER'] ) && ( is_numeric( $_REQUEST["MY_NUMBER']))) { $iVar = $_REQUEST['MY_NUMBER']; } $iCalculatedValue = $x / $iVar; thnx, Christoph