C# 发送邮箱携带附件

1.发送邮件本地可以，放到阿里云服务器上就不行了。
一般是服务器禁用了25端口。所以使用465端口发送邮箱。
25端口代码：

 public static void SendEmail(string strSmtpServer, string strFrom, string strFromPass, string strto, string strSubject, string strBody, bool isHtmlFormat, string[] files)
        {
            try
            {
                SmtpClient smtpClient = new SmtpClient(strSmtpServer);
                smtpClient.UseDefaultCredentials = false;
                smtpClient.Credentials = new NetworkCredential(strFrom, strFromPass);
                smtpClient.DeliveryMethod = SmtpDeliveryMethod.Network;
                MailMessage mailMessage = new MailMessage(strFrom, strto, strSubject, strBody);
                mailMessage.BodyEncoding = Encoding.Default;
                mailMessage.IsBodyHtml = isHtmlFormat;
                if (files != null)
                {
                    for (int i = 0; i < files.Length; i++)
                    {
                        if (File.Exists(files[i]))
                        {
                            mailMessage.Attachments.Add(new Attachment(files[i]));
                        }
                    }
                }

                smtpClient.Send(mailMessage);
            }
            catch (Exception ex)
            {
                throw new Exception("发送邮件失败。错误信息：" + ex.Message);
            }
        }

465端口代码：

/// <summary>
        /// 发送邮件
        /// </summary>
        /// <param name="mailHost">邮件服务器</param>
        /// <param name="mailPort">端口</param>
        /// <param name="mailName">发送邮件的用户名</param>
        /// <param name="mailPassword">发送邮件的密码</param>
        /// <param name="tomail">收件人邮箱地址</param>
        /// <param name="file">附件地址</param>
        /// <param name="subject">邮件主题</param>
        /// <param name="body">内容</param>
        public static void Sendmail(string mailHost, int mailPort, string mailName, string mailPassword, string tomail, List<string> file = null, string subject = "", string body = "")
        {
            try
            {
                System.Web.Mail.MailMessage mmsg = new System.Web.Mail.MailMessage();
                //验证  
                mmsg.Subject = subject;// "zhuti1";//邮件主题

                mmsg.BodyFormat = System.Web.Mail.MailFormat.Html;
                mmsg.Body = body;// "wqerwerwerwer";//邮件正文
                mmsg.BodyEncoding = Encoding.UTF8;//正文编码
                mmsg.Priority = System.Web.Mail.MailPriority.High;//优先级

                //添加邮件附件，可发送多个文件
                if (file != null && file.Count() > 0)
                {
                    foreach (var filename in file)
                    {
                        System.Web.Mail.MailAttachment mailAttach_1 = new System.Web.Mail.MailAttachment(filename);
                        mmsg.Attachments.Add(mailAttach_1);
                    }
                }
                mmsg.From = mailName;//发件者邮箱地址
                mmsg.To = tomail;//收件人收箱地址
                mmsg.Fields.Add("http://schemas.microsoft.com/cdo/configuration/smtpauthenticate", "1");
                //登陆名  
                mmsg.Fields.Add("http://schemas.microsoft.com/cdo/configuration/sendusername", mailName);
                //登陆密码  
                mmsg.Fields.Add("http://schemas.microsoft.com/cdo/configuration/sendpassword", mailPassword);
                mmsg.Fields.Add("http://schemas.microsoft.com/cdo/configuration/smtpserverport", 465);//端口 
                mmsg.Fields.Add("http://schemas.microsoft.com/cdo/configuration/smtpusessl", "true");
                System.Web.Mail.SmtpMail.SmtpServer = mailHost;
                System.Web.Mail.SmtpMail.Send(mmsg);
            }
            catch (Exception ex)
            {
                LogHelper.Info("Erro" + ex.ToString());
                throw new Exception("邮箱异常！" + ex.Message);
            }

        }