C# 多线程发送邮件 代码版

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最近在做项目时，发现项目中有个发邮件的代码，采用的是同步发送邮件，发送多人的话，性能不是一般的低，起初也没有想过改进这块代码，

现在项目上刚好有一个需求，也是发送邮件，而且是写在定时服务中，并且每次要发很多条邮件（上百条还是有的），思来想去，如果采用项目上同步的方式发送邮件，那岂不是要从中午十二点发送到晚上十二点？集团领导晚上十二点收到邮件，被打扰了，那么我的日子也就不长了，很有可能被炒鱿鱼哦。

为了不被炒鱿鱼，只能优化代码了。哈哈

其实，说实在的，原来的邮件发送代码不知道谁封装的，可读性奇差无比，用一个烂字来形容也不为过。

所以，还是自己来封装吧。

废话说多了，直接上代码吧，如下：

配置类：

    public class Constants
    {
        //邮件相关
        public static string mailSmtp = SelectHelper.GetFiled("mailSmtp");
        public static string mailSmtpPort = SelectHelper.GetFiled("mailSmtpPort");
        public static string mailFrom = SelectHelper.GetFiled("mailFrom");
        public static string mailFromPassword = SelectHelper.GetFiled("mailFromPassword");
    }

关于SelectHelper的用法，大家可参考我的博客：C# 自定义配置文件  

邮件发送类：

    public class SendMailHelper
    {
        public static string mailSmtp = Constants.mailSmtp;
        public static string mailSmtpPort = Constants.mailSmtpPort;
        public static string SmtpPassword = Constants.mailFromPassword;
        public static string mailFrom = Constants.mailFrom;
        /// <summary>
        /// 多线程发送邮件 开辟五个线程且异步
        /// </summary>
        /// <param name="MailToUsers">接收人邮箱 </param>
        /// <param name="Body">内容</param>
        /// <param name="Subject">主题</param>
        public static void SendMailToUser(List<SendMailHelperModel> lst)
        {
            try
            {
                Parallel.ForEach(lst, new ParallelOptions { MaxDegreeOfParallelism = 5 }, (item, pls, i) =>
                {
                    SendMail(item.MailToUsers, item.Subject, item.Body, item.AttachmentFilesList);
                });
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }

        /// <summary>
        /// 发送邮件
        /// </summary>
        /// <param name="MailTo">接收邮件的人 多人用逗号分离,譬如：King@xxx.com,Panda@xxx.com</param>
        private static void SendMail(string MailTo,string Subject,string Body, List<Attachment> AttachmentFilesList)
        {
            SmtpClient client = new SmtpClient(mailSmtp, Convert.ToInt32(mailSmtpPort));
            
            if (!(string.IsNullOrEmpty(mailFrom) || string.IsNullOrEmpty(SmtpPassword)))
            {
                client.Credentials = new NetworkCredential(mailFrom,
                                                           SmtpPassword,
                                                           null);
            }
            MailMessage mailMessage = new MailMessage(mailFrom, MailTo);
            mailMessage.Subject = Subject;
            mailMessage.Body = Body;
            mailMessage.IsBodyHtml = true;//是否是HTML邮件  
            if (AttachmentFilesList != null && AttachmentFilesList.Count > 0)
            {
                foreach (Attachment attachment in AttachmentFilesList)
                {
                    mailMessage.Attachments.Add(attachment);
                }
            }
            client.Send(mailMessage);
        }
    }

    public class SendMailHelperModel
    {
        public SendMailHelperModel()
        {
            AttachmentFilesList = new List<Attachment>();
        }
        /// <summary>
        /// 收件人集合
        /// </summary>
        public string MailToUsers { get; set; }
        /// <summary>
        /// 邮件主题
        /// </summary>
        public string Subject { get; set; }
        /// <summary>
        /// 邮件内容
        /// </summary>
        public string Body { get; set; }
        /// <summary>
        /// 邮件附件
        /// </summary>
        public List<Attachment> AttachmentFilesList { get; set; }
    }

配置文件：

<?xml version="1.0" encoding="utf-8"?>
<!--配置文件，用于配置项-->
<config>

  <!--邮件服务器smtp-->
  <dataConfig value="mailSmtp">smtp.163.com</dataConfig>
  <!--邮件服务器smtp端口号-->
  <dataConfig value="mailSmtpPort">25</dataConfig>
  <!--邮件发送人邮箱-->
  <dataConfig value="mailFrom">发件人邮箱</dataConfig>
  <!--邮件发送人密码-->
  <dataConfig value="mailFromPassword">发件人密码</dataConfig>
</config>

客户端代码如下：

        public void sendMails()
        {
            SendMailHelperModel M = new SendMailHelperModel();
            Attachment atm = new Attachment(@"D:SDP.zip");
            M.AttachmentFilesList.Add(atm);
            M.Body = "测试附件";
            M.MailToUsers = "Kin@movit-tech.com,Pan@movit-tech.com";
            M.Subject = "是否能收到附件";
            List<SendMailHelperModel> Mlist = new List<SendMailHelperModel>();
            Mlist.Add(M);
            SendMailHelper.SendMailToUser(Mlist);
        }

当然，本程序采用的是多线程，所以，在一次发送邮件次数不多的情况下，可用同步发送，当然也可以用Task.Run() 异步发送。

如果发送次数特别多，建议使用上述多线程发送。

如果有抄送人员，则代码如下：

客户端：

            try
            {
                List<SendMailHelperModel> Mlist = new List<SendMailHelperModel>();
                SendMailHelperModel M = new SendMailHelperModel();
                //内容
                M.Body = "你好<br/>测试邮件，请勿回复";
                //收件人，多人用逗号分隔
                M.MailToUsers = PriceLevelService.GetMailToUser();
                //抄送人员，多人用,分隔
                M.MailToCC = Constants.mailToCC;
                //主题
                M.Subject = "世茂网上招投标平台-价格水平完整性排查提醒";
                Mlist.Add(M);

                SendMailHelper.SendMailToUser(Mlist);
            }
            catch (Exception ex)
            {
                LogHelper.WriteTextLog(ex);
            }

邮件帮助类：

    public class SendMailHelper
    {
        public static string mailSmtp = Constants.mailSmtp;
        public static string mailSmtpPort = Constants.mailSmtpPort;
        public static string SmtpPassword = Constants.mailFromPassword;
        public static string mailFrom = Constants.mailFrom;

        /// <summary>
        /// 多线程发送邮件 开辟五个线程且异步
        /// </summary>
        /// <param name="MailToUsers">接收人邮箱 </param>
        /// <param name="MailToCC">抄送人</param>
        /// <param name="Body">内容</param>
        /// <param name="Subject">主题</param>
        public static void SendMailToUser(List<SendMailHelperModel> lst)
        {
            try
            {
                Parallel.ForEach(lst, new ParallelOptions { MaxDegreeOfParallelism = 5 }, (item, pls, i) =>
                {
                    SendMail(item.MailToUsers,item.MailToCC, item.Subject, item.Body, item.AttachmentFilesList);
                });
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }

        /// <summary>
        /// 接收邮件的人 多人用逗号分离,譬如：King@xxx.com,Panda@xxx.com
        /// </summary>
        /// <param name="MailTo">接收人 多人用逗号分离,譬如：King@xxx.com,Panda@xxx.com</param>
        /// <param name="MailToCC">抄送人</param>
        /// <param name="Subject"></param>
        /// <param name="Body"></param>
        /// <param name="AttachmentFilesList"></param>
        private static void SendMail(string MailTo, string MailToCC, string Subject,string Body, List<Attachment> AttachmentFilesList)
        {
            SmtpClient client = new SmtpClient(mailSmtp, Convert.ToInt32(mailSmtpPort));
            
            if (!(string.IsNullOrEmpty(mailFrom) || string.IsNullOrEmpty(SmtpPassword)))
            {
                client.Credentials = new NetworkCredential(mailFrom,
                                                           SmtpPassword,
                                                           null);
            }
            MailMessage mailMessage = new MailMessage(mailFrom, MailTo);
            mailMessage.CC.Add(MailToCC);
            mailMessage.Subject = Subject;
            mailMessage.Body = Body;
            mailMessage.IsBodyHtml = true;//是否是HTML邮件  
            if (AttachmentFilesList != null && AttachmentFilesList.Count > 0)
            {
                foreach (Attachment attachment in AttachmentFilesList)
                {
                    mailMessage.Attachments.Add(attachment);
                }
            }
            client.Send(mailMessage);
        }
    }

    public class SendMailHelperModel
    {
        public SendMailHelperModel()
        {
            AttachmentFilesList = new List<Attachment>();
        }
        /// <summary>
        /// 收件人集合
        /// </summary>
        public string MailToUsers { get; set; }
        /// <summary>
        /// 抄送人集合
        /// </summary>
        public string MailToCC { get; set; }
        /// <summary>
        /// 邮件主题
        /// </summary>
        public string Subject { get; set; }
        /// <summary>
        /// 邮件内容
        /// </summary>
        public string Body { get; set; }
        /// <summary>
        /// 邮件附件
        /// </summary>
        public List<Attachment> AttachmentFilesList { get; set; }
    }

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