Remove formatting from a string: “(123) 456-7890” => “1234567890”?

Question

I have a string when a telephone number is inputted - there is a mask so it always looks like \"(123) 456-7890\" - I\'d like to take the formatting out before saving it to the D

Answer 1

You can use a regular expression to remove all non-digit characters:

string phoneNumber = "(123) 456-7890";
phoneNumber = Regex.Replace(phoneNumber, @"[^\d]", "");

Then further on - depending on your requirements - you can either store the number as a string or as an integer. To convert the number to an integer type you will have the following options:

// throws if phoneNumber is null or cannot be parsed
long number = Int64.Parse(phoneNumber, NumberStyles.Integer, CultureInfo.InvariantCulture);

// same as Int64.Parse, but returns 0 if phoneNumber is null
number = Convert.ToInt64(phoneNumber);

// does not throw, but returns true on success
if (Int64.TryParse(phoneNumber, NumberStyles.Integer, 
       CultureInfo.InvariantCulture, out number))
{
    // parse was successful
}