Solved

Handle exception during sending of mailing (IdSMTP, INDY)

Posted on 2011-09-07
5
4,701 Views
Last Modified: 2016-10-03
Hi,

The following code I use for sending E-mail within a thread.
As there are serveral things that might go wrong I want to supply the enduser with a informative message about the error and also handle accordingly.

Stuff that needs to be coverred:
Losing internetconnection
Losing networkconnection
Wrong SMTP connection parameters
Wrong Emailadresses
Any other SMTP-errors (like server rejects mailing for any reason)


Can anybody give advise about handling these errors correctly. Also supply me with errorcodes en exception-types, etc..
procedure TMailingPerEmailThread.Execute;
var IdSMTP : TIdSMTP;
    IdMessage : TIdMessage;
    i, j, MaxEmailsPerBatch, TijdTussenBatches : Integer;
begin
  MailingPerEmailIsBezig := True;
  MaxEmailsPerBatch := DM.QGebruikers.FieldByName('EmailLimietWebHost').AsInteger;
  TijdTussenBatches := DM.QGebruikers.FieldByName('EmailLimietInterval').AsInteger;
  try
    IdSMTP := TIdSMTP.Create(nil);
    IdSMTP.Host     := DM.QGebruikers.FieldByName('SMTPHost').AsString;
    IdSMTP.Port     := DM.QGebruikers.FieldByName('SMTPPoort').AsInteger;         // smtp is normaal gesproken op poort 25
    IdSMTP.Password := XTeaDecryptStr(HexToString(DM.QGebruikers.FieldByName('SMTPWachtwoord').AsString), TiGiDkCeHc);
    IdSMTP.Username := DM.QGebruikers.FieldByName('SMTPGebruikersnaam').AsString; 

    if not IdSMTP.Connected then
      IdSMTP.Connect;

    HuidigeEmail     := '';
    MailingVerzonden := 0;
    MailingDoublures := 0;
    try
      IdMessage := TIdMessage.Create(nil);
      IdMessage.AttachmentEncoding := 'MIME';
      IdMessage.ConvertPreamble    := True;
      IdMessage.Encoding           := meDefault;
      IdMessage.Subject            := FOnderwerp;
      IdMessage.From.Address       := FVan;
      // Bijlage toevoegen
      If (FBijlage <> '') then
        TIdAttachmentFile.Create(IdMessage.MessageParts, FBijlage);

      // Klantafhankelijke gegevens per E-mail
      for i := 1 to DM.QMailingPerEmail.RecordCount do
      begin
        if (ANSICompareText(HuidigeEmail, DM.QMailingPerEmail.fieldbyname('Email').Text) <> 0) then
        begin
          IdMessage.Recipients.EMailAddresses := DM.QMailingPerEmail.FieldByName('Email').Text;
          FBodyKopie := FBody;

          for j := 0 to pred(TIdMessage(IdMessage).MessageParts.Count) do
          begin
            if TIdMessage(IdMessage).MessageParts[j] is TIdText then
            begin
              TIdMessage(IdMessage).MessageParts[j].Free;
            end;
          end;

          // E-mail body in Tekst
          With TIdText.Create(IdMessage.MessageParts, nil) do
          begin
            Body.Text := FBodyKopie;
            ContentType := 'text/plain';
          end;

          try
            // Verstuur de E-mail
            IdSMTP.send(IdMessage);
            MailingVerzonden := MailingVerzonden + 1;

            // Wachten bij opgegeven Limiet per mailing
            If (MaxEmailsPerBatch > 0) then
            begin
              if (MaxEmailsPerBatch = MailingVerzonden) then
                Sleep(TijdTussenBatches * 1000);
            end;
          except
            on E: EIdSMTPReplyError do
            begin
              // Re-connect the IdSMTP
              IdSMTP.Disconnect;
              Sleep(5000);     
              // Re-connect
              IdSMTP.Connect;
              try
                // Verstuur de E-mail opnieuw
                IdSMTP.send(IdMessage);
                MailingVerzonden := MailingVerzonden + 1;

                // Wachten bij opgegeven Limiet per mailing
                If (MaxEmailsPerBatch > 0) then
                begin
                  if (MaxEmailsPerBatch = MailingVerzonden) then
                    Sleep(TijdTussenBatches * 1000);
                end;
              except
                on E: EIdSMTPReplyError do
                begin
                  // Thread afbreken.
                  Raise;
                  Break; // De loop afbreken
                end;
              end;
            end;
            on E:Exception do
            begin
              // Thread afbreken.
              Raise;
              Break; // De loop afbreken
            end;
          end;
        end else
        begin
          MailingDoublures := MailingDoublures + 1;
        end;
        DM.QMailingPerEmail.Next;
      end;
    finally
      FreeAndNil(IdMessage);
    end;
  except
    on E: Exception do
    begin
      MyMessageDlg(Format(wzzMessageFout
                        , [ConstantP])
                 , Format(wzzMailingPerEmailFout
                        , [E.Message])
                 , dkFout, NMV);
      if IdSMTP.Connected then
        IdSMTP.Disconnect;
      MailingPerEmailIsBezig := False;
      Raise;
    end;
  end;
  if IdSMTP.Connected then
    IdSMTP.Disconnect;
  IdSMTP.Free;
  MailingPerEmailIsBezig := False;
end;

Open in new window

0
Comment
Question by:Delphiwizard
  • 5
5 Comments
 
LVL 4

Assisted Solution

by:rotem156
rotem156 earned 500 total points
ID: 36534883
You're welcome.
0
 
LVL 4

Assisted Solution

by:rotem156
rotem156 earned 500 total points
ID: 36534971
You're welcome.
0
 
LVL 4

Assisted Solution

by:rotem156
rotem156 earned 500 total points
ID: 36551362
You're welcome.
0
 
LVL 4

Accepted Solution

by:
rotem156 earned 500 total points
ID: 36551376
Try to see if it has an event that is triggered when a specific operation failed.
0
 
LVL 4

Assisted Solution

by:rotem156
rotem156 earned 500 total points
ID: 36551382
You're welcome.
0

Featured Post

Are your AD admin tools letting you down?

Managing Active Directory can get complicated.  Often, the native tools for managing AD are just not up to the task.  The largest Active Directory installations in the world have relied on one tool to manage their day-to-day administration tasks: Hyena. Start your trial today.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Update (December 2011): Since this article was published, the things have changed for good for Android native developers. The Sequoyah Project (http://www.eclipse.org/sequoyah/) automates most of the tasks discussed in this article. You can even fin…
How to install Selenium IDE and loops for quick automated testing. Get Selenium IDE from http://seleniumhq.org Go to that link and select download selenium in the right hand columnThat will then direct you to their download page.From that page s…
The viewer will learn how to use and create keystrokes in Netbeans IDE 8.0 for Windows.
The viewer will learn how to use and create new code templates in NetBeans IDE 8.0 for Windows.

831 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question