.Net发送邮件（注册发送邮件激活）的方法与注意要点

  public class SendEmail
    {
        /// <summary>
        ///     发送邮件：配置到web.config
        /// </summary>
        /// <param name="strto">收件人帐号</param>
        /// <param name="strSubject">主题</param>
        /// <param name="strBody">内容</param>
        public static void SendSMTPEMail(string strto, string strSubject, string strBody)
        {
            var strSmtpServer = ConfigurationManager.AppSettings["strSmtpServer"];
            var strFrom = ConfigurationManager.AppSettings["strFrom"];
            var strFromPass = ConfigurationManager.AppSettings["strFromPass"];
            if (string.IsNullOrEmpty(strSubject))
            {
                strSubject = ConfigurationManager.AppSettings["strSubject"];
            }
            var client = new SmtpClient(strSmtpServer);
            client.UseDefaultCredentials = false;
            client.Credentials =
                new NetworkCredential(strFrom, strFromPass);
            client.DeliveryMethod = SmtpDeliveryMethod.Network;

            var message =
                new MailMessage(strFrom, strto, strSubject, strBody);
            message.BodyEncoding = Encoding.UTF8;
            message.IsBodyHtml = true;
            client.Send(message);
        }

        /// <summary>
        ///     发送邮件
        /// </summary>
        /// <param name="strSmtpServer">如果是163邮箱就写:smtp.163.com </param>
        /// <param name="strFrom">发件人的帐号:xxx@163.com </param>
        /// <param name="strFromPass">发件人密码:使用加密的密码</param>
        /// <param name="strto">收件人帐号</param>
        /// <param name="strSubject">主题</param>
        /// <param name="strBody">内容</param>
        public static void SendSMTPEMail(string strSmtpServer, string strFrom, string strFromPass, string strto,
            string strSubject, string strBody)
        {
            var client = new SmtpClient(strSmtpServer);
            client.UseDefaultCredentials = false;
            client.Credentials =
                new NetworkCredential(strFrom, strFromPass);
            client.DeliveryMethod = SmtpDeliveryMethod.Network;

            var message =
                new MailMessage(strFrom, strto, strSubject, strBody);
            message.BodyEncoding = Encoding.UTF8;
            message.IsBodyHtml = true;
            client.Send(message);
        }
    }