Regular expression to match phone number?

Question

I want to match a phone number that can have letters and an optional hyphen:

• This is valid: 333-WELL
• This is also valid: 4URGENT

Answer 1

You seek the alternation operator, indicated with pipe character: |

However, you may need either 7 alternatives (1 for each hyphen location + 1 for no hyphen), or you may require the hyphen between 3rd and 4th character and use 2 alternatives.

One use of alternation operator defines two alternatives, as in:

({3,3}[0-9A-Za-z]-{4,4}[0-9A-Za-z]|{7,7}[0-9A-Za-z])