regex - Email validation, consecutive periods -

regex - Email validation, consecutive periods -

i using ^([a-za-z0-9_\-\.\']+)@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.)|(([a-za-z0-9\-]+\.)+))([a-za-z]{2,4}|[0-9]{1,3})(\]?)$ validate emails. regex not validating consecutive periods. can alter take consecutive periods?

regex