$price can contain only numbers & dot - how to check?

[notset]

Hello,

$price can contain only numbers or numbers with dot ('10', '9.99' and etc.).

How to validate this variable?

I can't use is_numeric(), because it returns true with '+' and some other symbols. I can't use ctype_digit() too, because it returns true only if the value is from numbers.

Please help.

[justsomeone]

you need to use regular expressions. Check the manual for ereg()

[laserlight]

You can validate with regex, or use something like:

function isValidPrice($price) {
	if ($parts = explode('.', $price)) {
		$count = count($parts);
		if ($count == 1) {
			return ctype_digit($parts[0]);
		} elseif ($count == 2) {
			return ctype_digit($parts[0]) && ctype_digit($parts[1]);
		} else {
			return false;
		}
	} else {
		return false;
	}
}

EDIT:
with regex, probably something like:

function isValidPrice($price) {
	return preg_match('/^[0-9]+(\.[0-9]+)?$/', $price);
}