You can specify a range of characters by using a hyphen.
I can't seem to work out which bit does what in the expression above - could somebody give me some pointers on how to edit this?Something like 0123456789876543210 would get through when it shouldn't. Joe, I can see your point, and yes it would be a dream to be validating if you knew the exact format of the number that was coming at you.However, without the intention of being smart here, I think it is development idealism to think we can add one more field to a form than absolutely necessary.The following table provides a complete list and description of the special characters that can be used in regular expressions.' by itself doesn't match any character; it forms the special word boundary character.
This chapter describes Java Script regular expressions.