Regular expression for email id

You can use RegExp function to validate email address in JavaScript. 

  function Isvalidemail(emailV) {
        if (emailV != null && emailV != undefined) {
            var pattern = new RegExp(/^[A-Z0-9._%+-]+@@([A-Z0-9-]+\.)+[A-Z]{2,4}$/i);
            return pattern.test(emailV);
        }
        else {
            return false;
        }
   }