First time regex, is this right?

[DEVILofDARKNESS]

It's the first time I used regex, so before I launch it on the WWW, I want to know if it's well formed and safe.

(It's an easy one, to check if the ammount of a textbox is a value above 0)

 

preg_match("/^[^-]?[1-9]+/", $_POST['ammount'], $matches)

[thebadbad]

Your pattern currently tries to match an optional character NOT a hyphen (at the very start of the string) followed by 1 or more digits being 1 to 9 (e.g. 110 wouldn't match). And anything could follow after that (so you would want to use a dollar sign that matches at the end of the string). If you strictly want to check for an integer above 0, you can use

 

~^[1-9][0-9]*$~D

 

But in that case you could obviously simply use built in functions:

 

if (ctype_digit($_POST['ammount']) && ((int) $_POST['ammount'] > 0))

[DEVILofDARKNESS]

Thanks