Regex for Comma Separated Number or Just Number

Question

This is something of a follow up from a previous question. The requirements have changed, and I\'m looking for some help with coming up with regex for either a comma separated n

Answer 1

Just add an "or one or more digits" to the end:

^(?:\d{1,3}(?:[,]\d{3})*|\d+)$

I think you had it almost right the first time and just didn't match up all your parentheses correctly.