how to check valid email with regex code example

Example 1: email regex

//Author: Mohammad Arman Khan
//Regular Expresssion for e-mail validation
var email_validator_regex = /^[a-zA-Z0-9.!#$%&'*+/=?^_`{|}~-]+@[a-zA-Z0-9-]+(?:\.[a-zA-Z0-9-]+)*$/;

Example 2: email validation regex

^([a-zA-Z0-9_\-\.]+)@([a-zA-Z0-9_\-\.]+)\.([a-zA-Z]{2,5})$