grep with regex for phone number

Question

I would like to get the phone numbers from a file. I know the numbers have different forms, I can handle for a single one, but don\'t know how to get a uniform regex. For ex

Answer 1

Try this one:

^(\d{10}|((([0-9]{3})\s){2})[0-9]{4}|((([0-9]{3})\-){2})[0-9]{4}|([(][0-9]{3}[)])[0-9]{3}[-][0-9]{4})$

This is only applicable for the formate you mention above like:

1. xxxxxxxxxx
2. xxx xxx xxxx
3. xxx-xxx-xxxx
4. (xxx)xxx-xxxx