Hello I have successfully created domain email validation. Please see attached photo.
In our organization we are using firstname.lastname@portal.com email format. (Note: Email domain is just for example only but our original format is just like that)
This code runs perfect, but it only validates the domain format which is @portal.com .
I want to validate something like this (firstname.lastname)
" firstname.lastname@portal.com " or "._ @portal.com "
Because some of our clients forgot to input “.” between their first name and last name. That makes their email address invalid already.
Thank you.
If you want to do the whole email address rather than just after the @, then you would be best looking at using regex to do this.
https://www.regular-expressions.info/email.html
https://www.w3resource.com/javascript/form/email-validation.php
https://stackoverflow.com/questions/46155/how-to-validate-an-email-address-in-javascript
https://www.regextester.com/19
However, the better option would be for the user to have to type the email address twice so that they have to make sure it matches.
You can also simply add a line of text informing users of how their email address should be entered, exactly like you have done in your post.
The last one is much more easier 
