(Delphi DLL) Fetch Full Email Given Email Header

When email headers are fetched using UIDs (not sequence numbers), then the resultant email object (containing only the header) will include auto-generated ckx-imap-* header fields to record information about the uid, attachments, etc. The IMAP UID of the email will be available in the "ckx-imap-uid" header. There will also be a "ckx-imap-isUid" header field having the value "YES" or "NO". If the email header was downloaded by UID, then "ckx-imap-isUID" will contain the value "YES" and the value of the "ckx-imap-uid" header field is the IMAP UID. If the "ckx-imap-isUID" header has a value of "NO", then the "ckx-imap-uid" header field represents the sequence number. (Sequence numbers of emails on the server can change over time, depending on whether emails are deleted. UIDs must be used to ensure that the correct full email is downloaded.)

The Chilkat Email object provides a GetImapUid method to return the UID from the ckx-imap-uid header. This can then be used to download the full email using the FetchSingle method. Assuming the UID is known, download a single email by UID from an IMAP mail server.

Chilkat for Delphi Downloads Chilkat non-ActiveX DLL for Delphi Chilkat ActiveX DLL for Delphi * The examples here use the non-ActiveX DLL.

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

...

procedure TForm1.Button1Click(Sender: TObject);
var
imap: HCkImap;
success: Boolean;
emailHeader: HCkEmail;
emailFull: HCkEmail;
uid: Integer;
isUid: Boolean;
uidFromCkxHeader: Integer;

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

imap := CkImap_Create();

// Connect to an IMAP server.
// Use TLS
CkImap_putSsl(imap,True);
CkImap_putPort(imap,993);
success := CkImap_Connect(imap,'imap.someMailServer.com');
if (success <> True) then
  begin
    Memo1.Lines.Add(CkImap__lastErrorText(imap));
    Exit;
  end;

// Login
success := CkImap_Login(imap,'***','***');
if (success <> True) then
  begin
    Memo1.Lines.Add(CkImap__lastErrorText(imap));
    Exit;
  end;

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

uid := 2014;
isUid := True;

// Fetch only the email header
emailHeader := CkImap_FetchSingleHeader(imap,uid,isUid);
if (CkImap_getLastMethodSuccess(imap) = True) then
  begin

    // Now fetch the full email
    uidFromCkxHeader := CkEmail_GetImapUid(emailHeader);
    if (uidFromCkxHeader < 0) then
      begin
        // Failed. 
        CkEmail_Dispose(emailHeader);
        Memo1.Lines.Add('No ckx-imap-uid header was found.');
        Exit;
      end;
    emailFull := CkImap_FetchSingle(imap,uidFromCkxHeader,True);
    if (CkImap_getLastMethodSuccess(imap) = True) then
      begin

        // OK, we have the full email, do whatever we want...

        CkEmail_Dispose(emailFull);
      end;

    CkEmail_Dispose(emailHeader);
  end;

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

CkImap_Dispose(imap);

end;