C#发送邮件及注意事项

        //参数配置
        static readonly string smtpServer = System.Configuration.ConfigurationManager.AppSettings["SmtpServer"];
        static readonly string userName = System.Configuration.ConfigurationManager.AppSettings["UserName"];
        static readonly string pwd = System.Configuration.ConfigurationManager.AppSettings["Pwd"];
        static readonly int smtpPort = Convert.ToInt32(System.Configuration.ConfigurationManager.AppSettings["SmtpPort"]);
        static readonly string authorName = System.Configuration.ConfigurationManager.AppSettings["AuthorName"];

        /// <summary>
        /// 发送邮件
        /// </summary>
        /// <param name="subject"></param>
        /// <param name="body"></param>
        /// <param name="email">接收人地址</param>
        public static void SendEmail(string subject, string body, string email)
        {
            try
            {
                List<string> toList = StringPlus.GetSubStringList(StringPlus.ToDBC(email), ',');
                OpenSmtp.Mail.Smtp smtp = new OpenSmtp.Mail.Smtp(smtpServer, userName, pwd, smtpPort);
                foreach (string s in toList)
                {
                    OpenSmtp.Mail.MailMessage msg = new OpenSmtp.Mail.MailMessage();
                    msg.From = new OpenSmtp.Mail.EmailAddress(userName, authorName);
                    msg.AddRecipient(s, OpenSmtp.Mail.AddressType.To);

                    //设置邮件正文,并指定格式为 html 格式
                    msg.HtmlBody = body;
                    //设置邮件标题
                    msg.Subject = subject;

                    //指定邮件正文的编码
                    msg.Charset = "gb2312";
                    //发送邮件
                    smtp.SendMail(msg);
                }
            }
            catch (Exception ex)
            {

            }
        }

注意事项：

端口号是25

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