验证EMAIL是否合法的函数，CodeIgniter Helper

verify_email_helper.php

<?php

// 验证邮箱地址是否合法
if ( ! function_exists('verify_email'))
{
  function verify_email($email)
	{
		$regex = "/^([\w\!\#$\%\&\'\*\+\-\/\=\?\^\`{\|\}\~]+\.)*[\w\!\#$\%\&\'\*\+\-\/\=\?\^\`{\|\}\~]+@((((([a-z0-9]{1}[a-z0-9\-]{0,62}[a-z0-9]{1})|[a-z0-9])\.)+[a-z]{2,6})|(\d{1,3}\.){3}\d{1,3}(\:\d{1,5})?)$/i";
		return preg_match($regex, $email) === 1;
	}
}