Pascal (Lazarus/Delphi)

Verify Email Recipients

A way to possibly determine valid/invalid email addresses. I would recommend being very careful about doing this because your IP address may be flagged as a potential spammer by the mail server (because you are probing for valid/invalid email addresses). This Chilkat functionality existed for many years, before this kind of activity became a problem. The functionality remains only because it is useful for some to test with their own SMTP servers. Pascal (Lazarus/Delphi)

program ChilkatDemo;

// Demonstrates using the Chilkat Pascal wrapper via the C bridge DLL.
// Builds as a console application under Lazarus (FPC) or Delphi.

{$IFDEF FPC}
  {$MODE DELPHI}
{$ENDIF}
{$APPTYPE CONSOLE}

uses
  {$IFDEF UNIX}
  cthreads,
  {$ENDIF}
  SysUtils,
  CkDllLoader,
  Chilkat.MailMan,
  Chilkat.StringArray,
  Chilkat.Email;

// ---------------------------------------------------------------------------

procedure RunDemo;
var
  success: Boolean;
  mailman: TMailMan;
  email: TEmail;
  badAddrs: TStringArray;
  i: Integer;

begin
  success := False;

  //  This example requires the Chilkat API to have been previously unlocked.
  //  See Global Unlock Sample for sample code.

  mailman := TMailMan.Create;

  //  SMTP connection settings...
  mailman.SmtpHost := 'smtp.example.com';
  mailman.SmtpUsername := 'MY_SMTP_USERNAME';
  mailman.SmtpPassword := 'MY_SMTP_PASSWORD';
  mailman.SmtpSsl := True;
  mailman.SmtpPort := 465;

  //  Create a new email object
  email := TEmail.Create;

  email.Subject := 'This is a test';
  email.Body := 'This is a test';
  email.From := 'myemail@example.com';
  success := email.AddTo('person1','person1@example.com');
  success := email.AddTo('person2','person2@example.com');
  success := email.AddTo('person3','person3@example.com');
  //  The SMTP server smtp.example.com won't know anything about an email address @somewhere_else.com
  success := email.AddTo('person3','person4@somewhere_else.com');
  //  ...

  //  Verify recipients.
  //  **** See the warning about using this API method in the description above.
  //  (An SMTP server only knows valid email address for its own domain.  For example,
  //  smtp.example.com *may* only know if person1@example.com is valid or invalid, but does
  //  not know anything about the validity of email addresses having other domains.)
  badAddrs := TStringArray.Create;
  success := mailman.VerifyRecips(email,badAddrs);
  if (success <> True) then
    begin
      WriteLn(mailman.LastErrorText);
      Exit;
    end;

  i := 0;
  while i < badAddrs.Count do
    begin
      WriteLn(badAddrs.GetString(i));
      i := i + 1;
    end;

  WriteLn('done.');


  mailman.Free;
  email.Free;
  badAddrs.Free;

end;

// ---------------------------------------------------------------------------

begin

  try
    RunDemo;
  except
    on E: Exception do
      WriteLn('Unhandled exception: ', E.ClassName, ': ', E.Message);
  end;

  WriteLn;
  {$IFDEF MSWINDOWS}
  WriteLn('Press Enter to exit...');
  ReadLn;
  {$ENDIF}
end.