After a quick research on the Stackoverflow, I wasn\'t able to find any solution for the multiple email validation using regex (split JS function is not applicable, but some
There is no reason not to use split - in the same way the backend will obviously do.
return str.split(/;\s*/).every(function(email) { return /.../.test(email); }
For good or not-so-good email regular expressions have a look at Validate email address in JavaScript?.