How to format this international phone number in Rails?

Question

If I have an international phone number such as this:

0541754301

how can I format it to produce something like this:

Answer 1

You can use regular expression to reformat the string. For the example you have given:

"0541754301".sub(/(\d{4})(\d{3})(\d{3})/, "\\1-\\2-\\3") # returns: "0541-754-301"