regular expressions only allow email code example

Example 1: email regex

[\w._%+-]+@[\w.-]+\.[a-zA-Z]{2,3}

Example 2: email regex

/^(([^<>()\[\]\\.,;:\s@"]+(\.[^<>()\[\]\\.,;:\s@"]+)*)|(".+"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/