.NET定时发送邮件

添加一个全局应用程序类Global.asax

代码会在访问网站时运行

Global.asax代码：

    void Application_Start(object sender, EventArgs e)
    {
        // 在应用程序启动时运行的代码
        System.Timers.Timer timer = new System.Timers.Timer(3600000);//设计时间间隔，如果一个小时执行一次就改为3600000
        timer.Elapsed += new System.Timers.ElapsedEventHandler(Send);
        timer.AutoReset = true;
        timer.Enabled = true;
    }

    void Application_End(object sender, EventArgs e)
    {
        //  在应用程序关闭时运行的代码
        System.Threading.Thread.Sleep(5000);
        string strUrl = "服务器地址";
        System.Net.HttpWebRequest _HttpWebRequest = (System.Net.HttpWebRequest)System.Net.WebRequest.Create(strUrl);
        System.Net.HttpWebResponse _HttpWebResponse = (System.Net.HttpWebResponse)_HttpWebRequest.GetResponse();
        System.IO.Stream _Stream = _HttpWebResponse.GetResponseStream();//得到回写的字节流
        _HttpWebResponse.Close();
    }

    void Application_Error(object sender, EventArgs e)
    {
        // 在出现未处理的错误时运行的代码

    }

    void Session_Start(object sender, EventArgs e)
    {
        // 在新会话启动时运行的代码

    }

    void Session_End(object sender, EventArgs e)
    {
        // 在会话结束时运行的代码。 
        // 注意: 只有在 Web.config 文件中的 sessionstate 模式设置为
        // InProc 时，才会引发 Session_End 事件。如果会话模式设置为 StateServer
        // 或 SQLServer，则不引发该事件。

    }

    private void Send(object sender, System.Timers.ElapsedEventArgs e)
    {
        switch (DateTime.Now.Hour)
        {
            case 0:
            case 24:
                SendEMail();
                break;
            //default:
            //    SendEMail();
            //    break;
        }
    }
    private void SendEMail()
    {
        string mailFrom = System.Configuration.ConfigurationManager.AppSettings["MailFrom"].ToString();
        string mailUser = System.Configuration.ConfigurationManager.AppSettings["MailUser"].ToString();
        string mailPassword = System.Configuration.ConfigurationManager.AppSettings["MailPassword"].ToString();
        string hostIP = System.Configuration.ConfigurationManager.AppSettings["MailHost"].ToString();

        List<string> mailAddress = new List<string>();
        string mailSubjct = "邮件主题";    
           string mailBody = "邮件内容:"；
           mailAddress.Add("邮件地址");string strReturn = sendMail(mailSubjct, mailBody, mailFrom, mailAddress, hostIP, mailUser, mailPassword, false);
    }

sendMail方法

public static string sendMail(string mailSubjct, string mailBody, string mailFrom, List<string> mailAddress, string hostIP, string username, string password, bool ssl)
        {
            string str = "";
            try
            {
                MailMessage message = new MailMessage
                {
                    IsBodyHtml = true,
                    Subject = mailSubjct,
                    Body = mailBody,

                    From = new MailAddress(mailFrom)
                };
                for (int i = 0; i < mailAddress.Count; i++)
                {
                    message.To.Add(mailAddress[i]);
                }
                SmtpClient client = new SmtpClient
                {
                    EnableSsl = ssl,
                    UseDefaultCredentials = false
                };
                NetworkCredential credential = new NetworkCredential(username, password);
                client.Credentials = credential;
                client.DeliveryMethod = SmtpDeliveryMethod.Network;
                client.Host = hostIP;
                client.Port = 0x19;
                client.Send(message);
            }
            catch (Exception exception)
            {
                str = exception.Message;
            }
            return str;
        }