Regular expression to not accept . at the end of the email address in React

Question

I want to construct a regular expression where . is not allowed as the last and first character of the email address (example: .abc.@gmail.com should not be accepted). Also, I have another requirement that .. 2 consecutives periods should not be allowed anywhere in the email address (example: abc...def@gmail.com ).

The regular expression that I am currently using is: let regEx = new RegExp(/^[a-zA-Z0-9+_.-]+@(\[(\d{1,3}\.)(([a-zA-Z\d-]+\.)+))([a-zA-Z]{2,15}|\d{1,3})(\]?)/); .

Can I get some help in modifying the above regular expression to fulfill my requirement?

PS: I have very little knowledge on regular expressions.

Answer 1

Adding your 2 new requirements we can try:

^(?!.*\.\.)[\p{L}\p{N}\s,_-][\p{L}\p{N}\s,._-]*[\p{L}\p{N}\s,_-]$

Explanation:

^                        from the start of the email
    (?!.*\.\.)           no two or more consecutive dots
    [\p{L}\p{N}\s,_-]    first character is not dot
    [\p{L}\p{N}\s,._-]*  zero or more allowed characters, including dot
    [\p{L}\p{N}\s,_-]    last character is not dot
$                        end of the email