Now I wanted to extend that and allow multiple mail-addresses to be added (just like MS Outlook, for example) with a semicolon as a mail-splitter.

It also allows a single email address that doesnt end in semicolon.

You can replace the final by to require at least one address.

To make it work as a validator you need to add at the beginning of the regex, and at the end.

This requires the semicolon if its not the end (because there are more than one address), but allows no semicolon if its the end.

Ive tested it. If it doesnt work for you get sure to trim spaces at the beggining and end of the expression.

Also if it is homework of some sort - make sure to add homework tag so people have better idea what type of answer would work best.

Should Email Addresses Be Separated By Comma Or Semicolon In Outlook Code Domain Names

For example, most TLDs are now using Unicode domain names, which are quite common in Europe.

For example, exampleexample.travel is a valid email address.

You could improve your answer by putting emphasis on the regex you used.

Provide details and share your research But avoid Asking for help, clarification, or responding to other answers.

Should Email Addresses Be Separated By Comma Or Semicolon In Outlook For Mac