#region ILogService 成员

        public void Write(string message)
        {
            lock (lockObj)
            {
                try
                {
                    string logFile = HttpContext.Current.Server.MapPath(string.Format("~/{0:yyyy-MM-dd}.log", DateTime.Now));
                    FileInfo fi = new FileInfo(logFile);
                    StreamWriter sw = null;
                    try
                    {
                        if (fi.Exists)
                            sw = fi.AppendText();
                        else
                            sw = fi.CreateText();

                        sw.WriteLine(">>>  " + DateTime.Now + "  <<<");
                        sw.WriteLine(message);
                        sw.WriteLine();
                        sw.Flush();
                    }
                    finally
                    {
                        if (sw != null)
                            sw.Close();
                    }
                }
                catch
                {
                    // do nothing.
                }
            }
        }

        #endregion
    }


发送邮件的接口：
    public class MailServiceImpl : IMailService
    {
        private string SmtpServer;
        private string MailFormAddress;
        private string MailUserName;
        private string MailPassWord;

        public MailServiceImpl()
        {
            //读取Email和接收邮件地址
            SmtpServer = ConfigurationManager.AppSettings["SMTPServer"].ToString();
            MailFormAddress = ConfigurationManager.AppSettings["MailFromAddress"].ToString();
            MailUserName = ConfigurationManager.AppSettings["MailUserName"].ToString();
            MailPassWord = ConfigurationManager.AppSettings["MailPassWord"].ToString();
        }

        #region IMailService 成员

        public bool SendResetPasswordLinkMail(string receiveEmail, string username, string resetlink)
        {
            try
            {
                SmtpClient client = null;
                string strFrom = MailFormAddress;
                string strTo = receiveEmail;
                string strBody = string.Format("Dear user: <br/>your accounts password reset request has been accepted.please click the following URL link to get your new password.<br/><a href='{0}'>{1}</a><br/>&nbsp;this link will expire in 24 hour.", resetlink, resetlink);
                string strSubject = "reset password link";

                //发送邮件
                client = new SmtpClient(SmtpServer);
                client.UseDefaultCredentials = false;
                client.Credentials = new System.Net.NetworkCredential(MailUserName, MailPassWord);
                client.DeliveryMethod = SmtpDeliveryMethod.Network;

                MailMessage mailmessage = new MailMessage(strFrom, strTo, strSubject, strBody);

                mailmessage.BodyEncoding = System.Text.Encoding.UTF8;
                mailmessage.IsBodyHtml = true;

                client.Send(mailmessage);

                return true;
            }
            catch (Exception ex)
            {
                LogException(ex);
                return false;
            }
        }

        private void LogException(Exception ex)
        {
            string msg = string.Format("Error Message: {0}\r\n{1}", ex.Message, ex.StackTrace);
            ServiceLocator.LogService.Write(msg);
        }

        /// <summary>
        /// 修改密码后发邮件
        /// </summary>
        /// <param name="receiveEmail"></param>
        /// <param name="newPassword"></param>
        /// <returns></returns>
        public bool SendSetPasswordSucessflyMail(string receiveEmail, string username, string newPassword)
        {
            try
            {
                SmtpClient client = null;
                string strFrom = MailFormAddress;
                string strTo = receiveEmail;
                string strBody = "your new password is:" + newPassword;
                string strSubject = "reset password!";

                //发送邮件
                client = new SmtpClient(SmtpServer);
                client.UseDefaultCredentials = false;
                client.Credentials = new System.Net.NetworkCredential(MailUserName, MailPassWord);
                client.DeliveryMethod = SmtpDeliveryMethod.Network;

                MailMessage mailmessage = new MailMessage(strFrom, strTo, strSubject, strBody);

                mailmessage.BodyEncoding = System.Text.Encoding.UTF8;
                mailmessage.IsBodyHtml = true;

                client.Send(mailmessage);

                return true;
            }
            catch (Exception ex)
            {
                LogException(ex);
                return false;
            }
        }

        /// <summary>
        /// 反馈发邮件
        /// </summary>
        /// <param name="receiveEmail"></param>
        /// <param name="content"></param>
        /// <returns></returns>
        public bool SendFeedbackMail(string sendEmail, string subject, string content)
        {
            try
            {
                SmtpClient client = null;
                string strFrom = MailFormAddress;
                string strTo = "Endusercare@lenovo.com";
                string strBody = string.Format("Email: {0}<br/><br/>Feedback: {1}", sendEmail, content);
                string strSubject = "GIS Portal Feedback: " + subject;

                //发送邮件
                client = new SmtpClient(SmtpServer);
                client.UseDefaultCredentials = false;
                client.Credentials = new System.Net.NetworkCredential(MailUserName, MailPassWord);
                client.DeliveryMethod = SmtpDeliveryMethod.Network;

                MailMessage mailmessage = new MailMessage(strFrom, strTo, strSubject, strBody);

                mailmessage.BodyEncoding = System.Text.Encoding.UTF8;
                mailmessage.IsBodyHtml = true;

                client.Send(mailmessage);

                return true;
            }
            catch (Exception ex)
            {
                LogException(ex);
                return false;
            }
        }

        #endregion