Question

Quick add on requirement in our project. A field in our DB to hold a phone number is set to only allow 10 characters. So, if I get passed ‘(913)-444-5555’ or anything else, is there a quick way to run a string through some kind of special replace function that I can pass it a set of characters to allow?

Regex?

Answer 1

Definitely regex:

string CleanPhone(string phone) {     Regex digitsOnly = new Regex(@'[^\d]');        return digitsOnly.Replace(phone, ''); } 

or within a class to avoid re-creating the regex all the time:

private static Regex digitsOnly = new Regex(@'[^\d]');     public static string CleanPhone(string phone) {     return digitsOnly.Replace(phone, ''); } 

Depending on your real-world inputs, you may want some additional logic there to do things like strip out leading 1’s (for long distance) or anything trailing an x or X (for extensions).