public static class EmailHelper  {    /// <summary>    /// 發送郵件    /// </summary>    /// <param name="subject">郵件主題</param>    /// <param name="msg">郵件內容</param>    /// <param name="filePath">附件地址，如果不添加附件傳null或""</param>    /// <param name="senderEmail">發送人郵箱地址</param>    /// <param name="senderPwd">發送人郵箱密碼</param>    /// <param name="recipientEmail">接收人郵箱</param>    public static void SendMail(string subject, string msg, string filePath, string senderEmail, string senderPwd, params string[] recipientEmail)    {      if (!CheckIsNotEmptyOrNull(subject, msg, senderEmail, senderPwd) || recipientEmail == null || recipientEmail.Length == 0)      {        throw new Exception("輸入信息無效");      }      try      {        string[] sendFromUser = senderEmail.Split('@');        //構造一個Email的Message對象        MailMessage message = new MailMessage();        //確定smtp服務器地址。實例化一個Smtp客戶端        System.Net.Mail.SmtpClient client = new System.Net.Mail.SmtpClient("smtp." + sendFromUser[1]);        //構造發件人地址對象        message.From = new MailAddress(senderEmail, sendFromUser[0], Encoding.UTF8);        //構造收件人地址對象        foreach (string userName in recipientEmail)        {          message.To.Add(new MailAddress(userName, userName.Split('@')[0], Encoding.UTF8));        }        if (!string.IsNullOrEmpty(filePath))        {          Attachment attach = new Attachment(filePath);          //得到文件的信息          ContentDisposition disposition = attach.ContentDisposition;          disposition.CreationDate = System.IO.File.GetCreationTime(filePath);          disposition.ModificationDate = System.IO.File.GetLastWriteTime(filePath);          disposition.ReadDate = System.IO.File.GetLastAccessTime(filePath);          //向郵件添加附件          message.Attachments.Add(attach);        }        //添加郵件主題和內容        message.Subject = subject;        message.SubjectEncoding = Encoding.UTF8;        message.Body = msg;        message.BodyEncoding = Encoding.UTF8;        //設置郵件的信息        client.DeliveryMethod = SmtpDeliveryMethod.Network;        message.BodyEncoding = System.Text.Encoding.UTF8;        message.IsBodyHtml = false;        //如果服務器支持安全連接，則將安全連接設為true。        //gmail,qq支持，163不支持        switch (sendFromUser[1])        {          case "gmail.com":          case "qq.com":            client.EnableSsl = true;            break;          default:            client.EnableSsl = false;            break;        }        //設置用戶名和密碼。        client.UseDefaultCredentials = false;        //用戶登陸信息        NetworkCredential myCredentials = new NetworkCredential(senderEmail, senderPwd);        client.Credentials = myCredentials;        //發送郵件        client.Send(message);      }      catch (Exception ex)      {        throw (ex);      }    }    /// <summary>    /// 驗證所有傳入字符串不能為空或null    /// </summary>    /// <param name="ps">參數列表</param>    /// <returns>都不為空或null返回true，否則返回false</returns>    public static bool CheckIsNotEmptyOrNull(params string[] ps)    {      if (ps != null)      {        foreach (string item in ps)        {          if (string.IsNullOrEmpty(item)) return false;        }        return true;      }      return false;    }  }