Pascal (Lazarus/Delphi)

Fetch 1st N Headers of Search Results

Calls Search to get a message set, then downloads the 1st N messages in the message set. There are two equivalent ways of doing it: (1) iterate from 0 to N-1 and download each message individually, or (2) create a new message set that contains the 1st N messages and pass it to FetchHeaders. Both are demonstrated here. 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.Imap,
  Chilkat.Email,
  Chilkat.MessageSet;

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

procedure RunDemo;
var
  success: Boolean;
  imap: TImap;
  fetchUids: Boolean;
  messageSet: TMessageSet;
  numFound: Integer;
  upperBound: Integer;
  i: Integer;
  bUid: Boolean;
  headerOnly: Boolean;
  email: TEmail;

begin
  success := False;

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

  imap := TImap.Create;

  //  Connect to an IMAP server.
  //  Use TLS
  imap.Ssl := True;
  imap.Port := 993;
  success := imap.Connect('imap.example.com');
  if (success = False) then
    begin
      WriteLn(imap.LastErrorText);
      Exit;
    end;

  //  Login
  success := imap.Login('****','****');
  if (success = False) then
    begin
      WriteLn(imap.LastErrorText);
      Exit;
    end;

  //  Select an IMAP mailbox
  success := imap.SelectMailbox('Inbox');
  if (success = False) then
    begin
      WriteLn(imap.LastErrorText);
      Exit;
    end;

  //  Get the message IDs of all the emails in the mailbox
  //  We can choose to fetch UIDs or sequence numbers.
  fetchUids := True;
  messageSet := TMessageSet.Create;
  success := imap.QueryMbx('ALL',fetchUids,messageSet);
  if (success = False) then
    begin
      WriteLn(imap.LastErrorText);
      Exit;
    end;

  numFound := messageSet.Count;
  if (numFound = 0) then
    begin
      WriteLn('No messages found.');
      Exit;
    end;

  //  Get the 1st 10 messages in messageSet.
  upperBound := 10;
  if (numFound < upperBound) then
    begin
      upperBound := numFound;
    end;

  i := 0;
  bUid := messageSet.HasUids;
  headerOnly := True;
  email := TEmail.Create;

  while i < upperBound do
    begin

      success := imap.FetchEmail(headerOnly,messageSet.GetId(i),bUid,email);
      if (success = False) then
        begin
          WriteLn(imap.LastErrorText);
          Exit;
        end;

      WriteLn(i + ': ' + email.Subject);

      i := i + 1;
    end;

  //  Disconnect from the IMAP server.
  success := imap.Disconnect();


  imap.Free;
  messageSet.Free;
  email.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.