Question

I need help writing a regex for a phone number pattern that allows the following formats for a phone number

1)###-###-####
or 
2)#-###-###-####
or
3)###-####
or
4)##########
or
5)#######

I am well aware, that you are able to find regex patterns on the internet, but I havent been able to find one that will pass for all these patterns.

I am using Java

Answer 1

You could use the | (or) operator and multiple patterns.

For example:
(\d{7})|(\d{10)| …