使用TLS从DELPHI(Indy)发送SMTP

begin
  IDSMTP1 := TIDSMTP.Create;
  IdSSLIOHandlerSocketopenSSL1 := TIdSSLIOHandlerSocketopenSSL.Create;
  try

    with IDSMTP1 do
    begin
      Host := srvr.Host;
      Port := srvr.Port;
      if (srvr.needAuthentication = 'Y') then
        AuthType := satDefault
      else
        AuthType := satNone;
      IOHandler := IdSSLIOHandlerSocketopenSSL1;

      if (srvr.secureMode = 'Y') then
        UseTLS := utUseRequireTLS
      else
        UseTLS := utNoTLSSupport;

      Username := srvr.Username;
      Password := srvr.Password;
    end;

    idMBHTML := TIdMessageBuilderHTML.Create;
    Idmessage1 := TIDMessage.Create;

    try
      with idMBHTML do
      begin
        enc := TEncoding.Unicode;
        HTML.LoadFromStream(FEmlMsg.MsgBody,enc);
        for c := 0 to FEmlMsg.Attachmnts.Count - 1 do
          Attachments.Add(FEmlMsg.Attachmnts[c]);
        FillMessage(IDMessage1);
      end;

      with Idmessage1 do
      begin
        Subject := FEmlMsg.MsgSubject;
        From.Address := FEmlMsg.FromAddress;
        From.Name := FEmlMsg.FromName;
        Recipients.EMailAddresses := FEmlMsg.RecipientAddress;
        if FEmlMsg.ReceiptRecipientAddress <> '' then
          ReceiptRecipient.Address := FEmlMsg.ReceiptRecipientAddress;
        if FEmlMsg.ReceiptRecipientName <> '' then
          ReceiptRecipient.Name := FEmlMsg.ReceiptRecipientName;
      end;

      with IDSMTP1 do
      begin
        if not Connected then
          Connect;
        Send(IdMessage1);
      end;

    finally
      Idmessage1.Free;
      idMBHTML.Free;
    end;
  finally
    IDSMTP1.Free;
    IdSSLIOHandlerSocketopenSSL1.Free;
  end;
end;