Delphi DLL

How to Download Messages in MessageSet One at a Time

See more IMAP Examples

If a message set contains a huge number of emails, it's NOT a good idea to try to download all at once into an email bundle using a method such as FetchBundle. It's better to iterate over the messages in the set to download one by one. Delphi DLL

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Imap, Email, MessageSet;

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Boolean;
imap: HCkImap;
fetchUids: Boolean;
messageSet: HCkMessageSet;
email: HCkEmail;
i: Integer;

begin
success := False;

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

imap := CkImap_Create();

// Connect using TLS.
CkImap_putSsl(imap,True);
CkImap_putPort(imap,993);
success := CkImap_Connect(imap,'imap.example.com');
if (success = False) then
  begin
    Memo1.Lines.Add(CkImap__lastErrorText(imap));
    Exit;
  end;

// Authenticate
success := CkImap_Login(imap,'email_account_login','email_account_password');
if (success = False) then
  begin
    Memo1.Lines.Add(CkImap__lastErrorText(imap));
    Exit;
  end;

// Select an IMAP mailbox
success := CkImap_SelectMailbox(imap,'Inbox');
if (success = False) then
  begin
    Memo1.Lines.Add(CkImap__lastErrorText(imap));
    Exit;
  end;

// Search for messages and return a set of matching messages.
// (This example will simply search for ALL messages.)
fetchUids := True;

messageSet := CkMessageSet_Create();
success := CkImap_QueryMbx(imap,'ALL',fetchUids,messageSet);
if (success = False) then
  begin
    Memo1.Lines.Add(CkImap__lastErrorText(imap));
    Exit;
  end;

Memo1.Lines.Add('Number of messages = ' + IntToStr(CkMessageSet_getCount(messageSet)));

email := CkEmail_Create();
i := 0;
while i < CkMessageSet_getCount(messageSet) do
  begin
    success := CkImap_FetchEmail(imap,False,CkMessageSet_GetId(messageSet,i),fetchUids,email);
    if (success = False) then
      begin
        Memo1.Lines.Add(CkImap__lastErrorText(imap));
        Exit;
      end;

    Memo1.Lines.Add(CkEmail__from(email) + '; ' + CkEmail__subject(email));

    i := i + 1;
  end;

Memo1.Lines.Add('OK');

CkImap_Dispose(imap);
CkMessageSet_Dispose(messageSet);
CkEmail_Dispose(email);

end;