Regex to fail email domain with two consecutive dots

Question

I am trying to validate the domain part of an email and I want to check that there is NOT two consecutive dots in the domain i.e. the following are not valid

Answer 1

You can use negative lookahead in front of your regex:

@(?!.*?\.\.)[^@]+$

Which will fail the match if 2 consecutive dots are present in domain anywhere.

[^@] will match 1 or more characters that are not @

RegEx Demo