[405hp]

Depends

In this context it works ok. If you want to call it from some other place in your code it won't be visible due to scope.

BTW validate_email($this->vEMail is not js.

FWIW Here is an email validation that uses regular expressions.

var sendto=prompt ('Enter your email address');
if ((sendto != null) && (sendto != ""))
  {
  emailRe = /^\w+([\.-]?\w+)*@\w+([\.-]?\w+)*\.(\w{2}|(com|net|org|edu|int|mil|gov|arpa|biz|aero|name|coop|info|pro|museum))$/;
  if (!emailRe.test(sendto.toLowerCase()))
      {
      alert(sendto + ' is an invalid email.');
      return(false);
      }