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Delphi DLL

Get IMAP UID from Email Header

See more IMAP Examples

Demonstrates how to get the IMAP UID from an email header. After fetching an email or header using IMAP, the UID is contained in the ckx-imap-uid header field.

Chilkat Delphi DLL Downloads

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

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Boolean;
imap: HCkImap;
fetchUids: Boolean;
messageSet: HCkMessageSet;
bundle: HCkEmailBundle;
headersOnly: Boolean;
email: HCkEmail;
msgSet1: HCkMessageSet;
i: Integer;
szBundle: Integer;
uidStr: PWideChar;

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 to an IMAP server.
// Use 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;

// Login
success := CkImap_Login(imap,'login','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;

fetchUids := True;
// Get the message UIDs of all the emails in the mailbox

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

bundle := CkEmailBundle_Create();
headersOnly := True;
success := CkImap_FetchMsgSet(imap,headersOnly,messageSet,bundle);
if (success = False) then
  begin
    Memo1.Lines.Add(CkImap__lastErrorText(imap));
    Exit;
  end;

// The UID of each fetched email header is available 
// in the ckx-imap-uid header field.
email := CkEmail_Create();
msgSet1 := CkMessageSet_Create();
i := 0;
szBundle := CkEmailBundle_getMessageCount(bundle);
while i < szBundle do
  begin
    CkEmailBundle_EmailAt(bundle,i,email);

    // Build a message set containing one UID
    uidStr := CkEmail__getHeaderField(email,'ckx-imap-uid');
    CkMessageSet_FromCompactString(msgSet1,uidStr);

    // Move this message to some other folder.
    success := CkImap_MoveMessages(imap,msgSet1,'someOtherFolder');
    if (success <> True) then
      begin
        Memo1.Lines.Add(CkImap__lastErrorText(imap));
        // Exit the loop...
        i := szBundle;
      end;
    i := i + 1;
  end;

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

CkImap_Dispose(imap);
CkMessageSet_Dispose(messageSet);
CkEmailBundle_Dispose(bundle);
CkEmail_Dispose(email);
CkMessageSet_Dispose(msgSet1);

end;