I have an html form with an input for a sales order number which should have the format of K1234/5678. It should always start with the letter K then 4 numbers, a / and followed by another set of 4 numbers.
I'm trying to validate the formatting using preg_match and I'm getting lost in the syntax of preg_match. From http://php.net/manual/en/function.preg-match.php I've gotten close. With the following code I'm able to verify that it contains at least 1 letter, some numbers and at least 1 non- alphanumeric value.
$so= $_POST['so'];
if (preg_match(""/^(?=.*[a-z]{1})(?=.*[0-9]{4})(?=.*[^a-z0-9]{1})/i", $so))
{
print $so;
}
What is the correct syntax to use for this? Is preg_match even the best way to do this?