验证邮箱正则表达式，包含二级域名邮箱，手机号正则表达式支持170号段

function CheckEmail(email){
     if (/^[0-9a-z][a-z0-9\._-]{1,}@[a-z0-9-]{1,}[a-z0-9](\.[a-z]{1,})+$/.test(email) {
        return true;
     }
     return false;
}

class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine(CheckEmail("xxx@vip"));
            Console.WriteLine(CheckEmail("xxx@vip.qq.com"));
            Console.WriteLine(CheckEmail("xxxxx@qq.com"));
        }

        public static bool CheckEmail(string email)
        {
            Regex reg = new Regex(@"[0-9a-z][a-z0-9\._-]{1,}@[a-z0-9-]{1,}[a-z0-9](\.[a-z]{1,})+", RegexOptions.IgnoreCase);
            if (reg.IsMatch(email))
            {
                return true;
            }
            return false;
        }
    }