發送支持html標籤的郵件

       /// <summary>
       ///
       /// </summary>
       /// <param name="mailContent">內容</param>
       /// <param name="toaddress">目標地址</param>
       /// <param name="fromaddress">發送地址</param>
       /// <param name="fromaddressname">發送地址顯示名</param>
       /// <param name="fromMailPassword">發送地址密碼</param>
       /// <param name="mailSub">標題</param>
       /// <param name="smtpServer"></param>

 public void SendHtmlMail(string mailContent, string toaddress, string fromaddress, string fromaddressname, string fromMailPassword, string mailSub, string smtpServer,int smtpPort ,bool ssl)
        {

 System.Net.Mail.MailMessage msg = new System.Net.Mail.MailMessage();

            msg.To.Add(toaddress);//添加單一收信地址

            msg.To.Add(fromaddress);

 msg.From = new System.Net.Mail.MailAddress(fromaddress, fromaddressname, System.Text.Encoding.UTF8);
            /* 上面3個參數分別是發件人地址（可以隨便寫），發件人姓名，編碼*/
            msg.Subject = mailSub;

 msg.SubjectEncoding = System.Text.Encoding.UTF8;//郵件標題編碼
            //long tol = GateCount + HandCount;
            msg.Body = mailContent;
            msg.BodyEncoding = System.Text.Encoding.UTF8;//郵件內容編碼
            msg.IsBodyHtml = true;//是否是HTML郵件

msg.Priority = MailPriority.High;
            SmtpClient client = new SmtpClient(smtpServer, smtpPort);
            //身份認證
            NetworkCredential crendetial = new NetworkCredential(fromaddress, fromMailPassword);
            client.Credentials = crendetial;
            client.EnableSsl = ssl;

 object userState = msg;
            client.SendAsync(msg,null);//開始發送
        }

        /// <summary>
       ///
       /// </summary>
       /// <param name="mailContent">內容</param>
       /// <param name="toaddress">目標地址</param>
       /// <param name="mailSub">標題</param>

public bool SendHtmlMail(string toaddress, string mailSub, string mailContent)
        {
            try
            {
                SendHtmlMail(mailContent, toaddress, _userID, _userName, _pwd, mailSub, _smtpServer, _smtpPort, _ssl);
            }
            catch (Exception ex)
            {
                return false;
            }
            return true;
        }

   //身份認證
            NetworkCredential crendetial = new NetworkCredential(fromaddress, fromMailPassword);這句話很重要，少了身份認證可能會出現有的電腦等發送有的卻無任何反應