Parse Phone Number into component parts

Question

I need a well tested Regular Expression (.net style preferred), or some other simple bit of code that will parse a USA/CA phone number into component parts, so:

• 3035551234122
• 1-303-555-1234x122
• (303)555-1234-122
• 1 (303) 555 -1234-122

etc...

all parse into:

• AreaCode: 303
• Exchange: 555
• Suffix: 1234
• Extension: 122

Answer 1

This is the one I use:

^(?:(?:[\+]?(?<CountryCode>[\d]{1,3}(?:[ ]+|[\-.])))?[(]?(?<AreaCode>[\d]{3})[\-/)]?(?:[ ]+)?)?(?<Number>[a-zA-Z2-9][a-zA-Z0-9 \-.]{6,})(?:(?:[ ]+|[xX]|(i:ext[\.]?)){1,2}(?<Ext>[\d]{1,5}))?$

I got it from RegexLib I believe.

Answer 2

Strip out anything that's not a digit first. Then all your examples reduce to:

/^1?(\d{3})(\d{3})(\d{4})(\d*)$/

To support all country codes is a little more complicated, but the same general rule applies.

Answer 3

This regex works exactly as you want with your examples:

Regex regexObj = new Regex(@"\(?(?<AreaCode>[0-9]{3})\)?[-. ]?(?<Exchange>[0-9]{3})[-. ]*?(?<Suffix>[0-9]{4})[-. x]?(?<Extension>[0-9]{3})");
Match matchResult = regexObj.Match("1 (303) 555 -1234-122");

// Now you have the results in groups 
matchResult.Groups["AreaCode"];
matchResult.Groups["Exchange"];
matchResult.Groups["Suffix"];
matchResult.Groups["Extension"];