// The following example codes demonstrate marking email as read/downloaded on POP3 server
// To get full sample projects, please download and install EAGetMail on your machine.
// To run it correctly, please change email server, user, password, folder, file name value to yours

Unit Unit1; 

Interface 

Uses 
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms, 
  Dialogs, StdCtrls, StrUtils, EAGetMailObjLib_TLB; 

Type 
  TForm1 = Class(TForm) 
    Button1: TButton; 
    Procedure Button1Click(Sender: TObject); 

    // UIDL functions
    Procedure LoadUIDL(); 
    Procedure UpdateUIDL(); 
    Procedure SyncUIDL( oServer: TMailServer; infos: OleVariant); 
    Function FindExistedUIDL( oServer: TMailServer; UIDL: WideString ): Boolean; 
    Procedure AddUIDL( oServer: TMailServer; UIDL: WideString ); 

  private 
    { Private declarations } 
  public 
    { Public declarations } 
  End; 

Const 
  MailServerPop3 = 0; 
  MailServerImap4 = 1; 

Var 
  Form1: TForm1; 
  m_curpath: WideString; 
  m_uidlfile: WideString; 
  m_uidls: WideString; 

Implementation 

{$R *.dfm} 

Procedure TForm1.LoadUIDL(); 
Var 
  oTools: TTools; 
Begin 
  oTools := TTools.Create(Application); 
  m_uidls := ''; 
  m_uidls := oTools.ReadTextFile(m_uidlfile, 0); 
End; 

Procedure TForm1.UpdateUIDL(); 
Var 
  oTools: TTools; 
Begin 
  Try 
    oTools := TTools.Create(Application); 
    oTools.WriteTextFile( m_uidlfile, m_uidls, 0 ); 
  Except 
    On ep:Exception Do 
    ShowMessage( 'Update UIDL Error: ' + ep.Message ); 
  End; 
End; 

Procedure TForm1.SyncUIDL( oServer: TMailServer; infos: OleVariant); 
Var 
  index, i, UBound: Integer; 
  curpref, uidlpref, t, localuidl: WideString; 
  uidls, newuidls: WideString; 
  bRemove, bExistOnServer: boolean; 
  oInfo: IMailInfo; 
Begin 
  uidlpref := LowerCase(oServer.Server) + '#' + 
      LowerCase(oServer.User) + ' '; 

  uidls := m_uidls; 
  UBound := VarArrayHighBound(infos, 1 ); 

  While true Do 
  Begin 
    index := Pos( #13#10, uidls ); 
    If( index <= 0 ) Then 
      break; 

    t := LeftStr(uidls, index-1); 
    uidls := MidStr( uidls, index + 2, Length(uidls)-index-2); 
    bRemove := false; 
    If Length(t) > Length(uidlpref) Then 
    Begin 
      curpref := LeftStr(t, Length(uidlpref)); 
      // this UIDL belongs to current server/user
      If CompareStr(curpref, uidlpref) = 0 Then 
      Begin 
        localuidl := MidStr( t, Length(curpref)+1, Length(t)-Length(curpref)); 
        bExistOnServer := false; 
        For i := 0 To UBound Do 
        Begin 
          oInfo := IDispatch(VarArrayGet(infos, i)) As IMailInfo; 
          If CompareStr(oInfo.UIDL, localuidl ) = 0 Then 
            Begin 
              bExistOnServer := true; 
              break; 
            End; 
        End; 

        If Not bExistOnServer Then 
          bRemove := true; 

        If trim(t) = '' Then 
          bRemove := true; 
      End; 
    End; 

    If Not bRemove Then 
      newuidls := newuidls + t + #13#10; 
  End; 

  m_uidls := newuidls; 
End; 

Function TForm1.FindExistedUIDL( oServer: TMailServer; UIDL: WideString ): Boolean; 
Var 
  s: WideString; 
  index: Integer; 
Begin 
  s := LowerCase(oServer.Server) + '#' + 
      LowerCase(oServer.User) + ' ' + UIDL + #13#10; 

  index := Pos( s, m_uidls ); 
  If index > 0 Then 
    FindExistedUIDL := true 
  Else 
    FindExistedUIDL := false; 
End; 

Procedure TForm1.AddUIDL( oServer: TMailServer; UIDL: WideString ); 
Begin 
  m_uidls := m_uidls + LowerCase(oServer.Server) + '#' + 
      LowerCase(oServer.User) + ' ' + UIDL + #13#10; 
End; 
Function TForm1.SearchFolder(folders: OleVariant; name: WideString) 
:IImap4Folder; 
Var 
  i, UBound: Integer; 
  folder: IImap4Folder; 
Begin 
  UBound := VarArrayHighBound(folders, 1 ); 
  For i:= 0 To UBound Do 
  Begin 
    folder := IDispatch(VarArrayGet(folders,i)) As IImap4Folder; 
    If CompareText( folder.Name, name ) = 0 Then 
    Begin 
      Result := folder; 
      exit; 
    End; 

    // Search folder in sub-folders
    folder := SearchFolder( folder.SubFolders, name ); 
    If Not (folder = nil ) Then 
    Begin 
        Result := folder; 
        exit; 
    End; 
  End; 
  // No folder found
  Result := nil; 
End; 

Procedure TForm1.Button1Click(Sender: TObject); 
Var 
  oMail: IMail; 
  oClient: TMailClient; 
  oServer: TMailServer; 
  oTools: TTools; 
  infos: OleVariant; 
  i, UBound, Count: Integer; 
  oInfo: IMailInfo; 
  mailFolder: WideString; 
  fileName: WideString; 
  leaveCopy: Boolean; 
Begin 
  Try 
    oTools := TTools.Create(Application); 

    // Create a folder named "inbox" under
    // current directory to store the email files
    mailFolder := GetCurrentDir() + '\inbox'; 
    m_curpath := GetCurrentDir(); 
    m_uidlfile := m_curpath + '\uidl.txt'; 
    oTools.CreateFolder(mailFolder); 

    oServer := TMailServer.Create(Application); 
    oServer.Server := 'pop3.emailarchitect.net'; 
    oServer.User := 'test@emailarchitect.net'; 
    oServer.Password := 'testpassword'; 
    oServer.Protocol := MailServerPop3; 

    // If your server requires SSL connection
    // Please add the following codes
    // oServer.SSLConnection := true;
    // oServer.Port := 995;

    // leave a copy of message on server
    leaveCopy := true; 
    oClient := TMailClient.Create(Application); 
    oClient.LicenseCode := 'TryIt'; 

    oClient.Connect1(oServer.DefaultInterface); 
    ShowMessage( 'Connected!' ); 

    // UIDL is the identifier of every email on POP3/IMAP4 server, to avoid retrieve
    // the same email from server more than once, we record the email uidl retrieved every time
    // if you delete the email from server every time and not to leave a copy of email on
    // the server, then please remove all the function about uidl.
    LoadUIDL(); 

    infos := oClient.GetMailInfos(); 
    UBound := VarArrayHighBound( infos, 1 ); 
    Count := UBound+1; 

    SyncUIDL( oServer, infos ); 

    ShowMessage(Format('Total %d email(s)', [Count])); 

    For i := 0 To UBound Do 
    Begin 
      oInfo := IDispatch(VarArrayGet(infos, i)) As IMailInfo ; 
      ShowMessage(Format('Index: %d; Size: %d; UIDL: ' + oInfo.UIDL, 
      [oInfo.Index, oInfo.Size])); 

      If FindExistedUIDL(oServer, oInfo.UIDL) Then 
          continue; // this email has been downloaded, Do Not receive it again 

      // Generate a random file name by current local datetime,
      // You can use your method to generate the filename if you do not like it
      fileName := mailFolder + '\' + oTools.GenFileName(i) + '.eml; 

      // Receive email from POP3 server
      oMail := oClient.GetMail( oInfo ); 

      ShowMessage( 'From: ' + oMail.From.Address + #13#10 + 
        'Subject: ' + oMail.Subject ); 

      // Save email to local disk
      oMail.SaveAs( fileName, true ); 

      If leaveCopy Then 
      Begin 
          //add the email uidl to uidl file to avoid we retrieve it next time.
          AddUIDL( oServer, oInfo.UIDL ); 
      End 
      Else 
      Begin 
        // Mark email as deleted from IMAP4 server
        oClient.Delete(oInfo); 
      End; 
    End; 

    // Quit and pure emails marked as deleted from POP3 server
    oClient.Quit; 

  Except 
    On ep:Exception Do 
      ShowMessage( 'Error: ' + ep.Message ); 
  End; 

  UpdateUIDL(); 

End; 

End.