www.pudn.com > pop3cli.zip > MAILRCV1.PAS


{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * 
 
Author:       François PIETTE 
Object:       Show how to use TPop3Cli (POP3 protocol, RFC-1225) 
Creation:     03 october 1997 
Version:      1.02 
EMail:        francois.piette@pophost.eunet.be    francois.piette@rtfm.be 
              http://www.rtfm.be/fpiette 
Support:      Use the mailing list twsocket@rtfm.be See website for details. 
Legal issues: Copyright (C) 1997, 1998 by François PIETTE 
              Rue de Grady 24, 4053 Embourg, Belgium. Fax: +32-4-365.74.56 
               
 
              This software is provided 'as-is', without any express or 
              implied warranty.  In no event will the author be held liable 
              for any  damages arising from the use of this software. 
 
              Permission is granted to anyone to use this software for any 
              purpose, including commercial applications, and to alter it 
              and redistribute it freely, subject to the following 
              restrictions: 
 
              1. The origin of this software must not be misrepresented, 
                 you must not claim that you wrote the original software. 
                 If you use this software in a product, an acknowledgment 
                 in the product documentation would be appreciated but is 
                 not required. 
 
              2. Altered source versions must be plainly marked as such, and 
                 must not be misrepresented as being the original software. 
 
              3. This notice may not be removed or altered from any source 
                 distribution. 
 
Updates: 
Nov 12, 1997  V1.01 Added a GetAll button to get all messages waiting in the 
              POP3 server, copying them to a file using the UIDL to build 
              the file name (sorry, wont work with D1 because of long file 
              name). The message is *NOT* deleted from the POP3 server. 
Jan 10, 1998  V1.02 Added port selection 
 
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
unit MailRcv1; 
 
interface 
 
uses 
  WinTypes, WinProcs, Messages, SysUtils, Classes, Graphics, Controls, Forms, 
  Dialogs, ExtCtrls, StdCtrls, IniFiles, Pop3Prot; 
 
const 
    PopTstVersion = 102; 
 
type 
  TPOP3ExcercizerForm = class(TForm) 
    DisplayMemo: TMemo; 
    Panel1: TPanel; 
    InfoLabel: TLabel; 
    Label1: TLabel; 
    Label2: TLabel; 
    Label3: TLabel; 
    Label4: TLabel; 
    Label5: TLabel; 
    ConnectButton: TButton; 
    QuittButton: TButton; 
    UserButton: TButton; 
    HostEdit: TEdit; 
    UserNameEdit: TEdit; 
    PassWordEdit: TEdit; 
    PassButton: TButton; 
    MsgNumEdit: TEdit; 
    RetrButton: TButton; 
    StatButton: TButton; 
    ListAllButton: TButton; 
    ListButton: TButton; 
    DeleteButton: TButton; 
    NoopButton: TButton; 
    LastButton: TButton; 
    ResetButton: TButton; 
    TopButton: TButton; 
    MsgLinesEdit: TEdit; 
    RpopButton: TButton; 
    UidlButton: TButton; 
    ApopButton: TButton; 
    NextButton: TButton; 
    GetAllButton: TButton; 
    PortEdit: TEdit; 
    Label6: TLabel; 
    Pop3Client: TPop3Cli; 
    OpenButton: TButton; 
    procedure ConnectButtonClick(Sender: TObject); 
    procedure FormCreate(Sender: TObject); 
    procedure QuittButtonClick(Sender: TObject); 
    procedure UserButtonClick(Sender: TObject); 
    procedure PassButtonClick(Sender: TObject); 
    procedure Pop3ClientMessageBegin(Sender: TObject); 
    procedure Pop3ClientMessageEnd(Sender: TObject); 
    procedure Pop3ClientMessageLine(Sender: TObject); 
    procedure RetrButtonClick(Sender: TObject); 
    procedure StatButtonClick(Sender: TObject); 
    procedure ListAllButtonClick(Sender: TObject); 
    procedure ListButtonClick(Sender: TObject); 
    procedure Pop3ClientListBegin(Sender: TObject); 
    procedure Pop3ClientListEnd(Sender: TObject); 
    procedure Pop3ClientListLine(Sender: TObject); 
    procedure DeleteButtonClick(Sender: TObject); 
    procedure NoopButtonClick(Sender: TObject); 
    procedure LastButtonClick(Sender: TObject); 
    procedure ResetButtonClick(Sender: TObject); 
    procedure TopButtonClick(Sender: TObject); 
    procedure RpopButtonClick(Sender: TObject); 
    procedure FormCloseQuery(Sender: TObject; var CanClose: Boolean); 
    procedure Pop3ClientDisplay(Sender: TObject; Msg: String); 
    procedure UidlButtonClick(Sender: TObject); 
    procedure Pop3ClientUidlBegin(Sender: TObject); 
    procedure Pop3ClientUidlEnd(Sender: TObject); 
    procedure Pop3ClientUidlLine(Sender: TObject); 
    procedure ApopButtonClick(Sender: TObject); 
    procedure NextButtonClick(Sender: TObject); 
    procedure GetAllButtonClick(Sender: TObject); 
    procedure Pop3ClientRequestDone(Sender: TObject; RqType: TPop3Request; 
      Error: Word); 
    procedure OpenButtonClick(Sender: TObject); 
  private 
    FFile        : TextFile; 
    FFileName    : String; 
    FFileOpened  : Boolean; 
    FGetAllState : Integer; 
    FMsgPath     : String; 
    procedure Exec(MethodPtr  : TPop3NextProc; 
                   MethodName : String); 
    procedure MessageBegin(Sender: TObject); 
    procedure MessageLine(Sender: TObject); 
    procedure GetAllMessageLine(Sender: TObject); 
    procedure GetAllRequestDone(Sender: TObject; 
                                RqType: TPop3Request; Error: Word); 
    procedure NextMessageRequestDone(Sender: TObject; 
                                     RqType: TPop3Request; Error: Word); 
  public 
    { Déclarations publiques } 
  end; 
 
var 
  POP3ExcercizerForm: TPOP3ExcercizerForm; 
 
implementation 
 
{$R *.DFM} 
 
uses 
    MailRcv2; 
 
const 
    IniFileName = 'MAILRCV.INI'; 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
{ Restore some data from the INI file                                       } 
procedure TPOP3ExcercizerForm.FormCreate(Sender: TObject); 
var 
    IniFile : TIniFile; 
begin 
    IniFile := TIniFile.Create(IniFileName); 
    HostEdit.Text     := IniFile.ReadString('Data', 'Host',     ''); 
    PortEdit.Text     := IniFile.ReadString('Data', 'Port',     ''); 
    UserNameEdit.Text := IniFile.ReadString('Data', 'UserName', ''); 
    PassWordEdit.Text := IniFile.ReadString('Data', 'Password', ''); 
    IniFile.Free; 
    InfoLabel.Caption := ''; 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
{ Save data to INI file                                                     } 
procedure TPOP3ExcercizerForm.FormCloseQuery(Sender: TObject; 
  var CanClose: Boolean); 
var 
    IniFile : TIniFile; 
begin 
    IniFile := TIniFile.Create(IniFileName); 
    IniFile.WriteString('Data', 'Host',     HostEdit.Text); 
    IniFile.WriteString('Data', 'Port',     PortEdit.Text); 
    IniFile.WriteString('Data', 'UserName', UserNameEdit.Text); 
    IniFile.WriteString('Data', 'Password', PassWordEdit.Text); 
    IniFile.Free; 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
{ This event handler is called when the TPop3Client object wants to display } 
{ some information such as connection progress or errors.                   } 
procedure TPOP3ExcercizerForm.Pop3ClientDisplay(Sender: TObject; 
  Msg: String); 
begin 
    DisplayMemo.Lines.Add(Msg); 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
{ All the TPop3Client method are of the same type. To simplify this demo    } 
{ application, Exec transfert the parameters form the various EditBoxes     } 
{ to the Pop3Client instance and then call the appropriate method, showing  } 
{ the result in the InfoLabel.Caption.                                      } 
procedure TPOP3ExcercizerForm.Exec( 
    MethodPtr  : TPop3NextProc; 
    MethodName : String); 
begin 
    Pop3Client.Host           := HostEdit.Text; 
    Pop3Client.Port           := PortEdit.Text; 
    Pop3Client.UserName       := UserNameEdit.Text; 
    Pop3Client.PassWord       := PassWordEdit.Text; 
    Pop3Client.MsgNum         := StrToInt(MsgNumEdit.Text); 
    Pop3Client.MsgLines       := StrToInt(MsgLinesEdit.Text); 
    { We need to reassign event handlers because we may have changed them } 
    { doing GetAllMessages for example                                    } 
    Pop3Client.OnRequestDone  := Pop3ClientRequestDone; 
    Pop3Client.OnMessageBegin := Pop3ClientMessageBegin; 
    Pop3Client.OnMessageEnd   := Pop3ClientMessageEnd; 
    Pop3Client.OnMessageLine  := Pop3ClientMessageLine; 
    InfoLabel.Caption         := MethodName + ' started'; 
    try 
        MethodPtr; 
        InfoLabel.Caption := MethodName + ' ok'; 
    except 
        on E:Exception do begin 
            InfoLabel.Caption := MethodName + ' failed (' + E.Message + ')'; 
        end; 
    end; 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
procedure TPOP3ExcercizerForm.ConnectButtonClick(Sender: TObject); 
begin 
    Exec(Pop3Client.Connect, 'Connect'); 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
procedure TPOP3ExcercizerForm.OpenButtonClick(Sender: TObject); 
begin 
    Exec(Pop3Client.Open, 'Open'); 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
procedure TPOP3ExcercizerForm.UserButtonClick(Sender: TObject); 
begin 
    Exec(Pop3Client.User, 'User'); 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
procedure TPOP3ExcercizerForm.PassButtonClick(Sender: TObject); 
begin 
    Exec(Pop3Client.Pass, 'Pass'); 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
procedure TPOP3ExcercizerForm.QuittButtonClick(Sender: TObject); 
begin 
    Exec(Pop3Client.Quit, 'Quit'); 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
procedure TPOP3ExcercizerForm.RetrButtonClick(Sender: TObject); 
begin 
    Exec(Pop3Client.Retr, 'Retr'); 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
procedure TPOP3ExcercizerForm.StatButtonClick(Sender: TObject); 
begin 
    Exec(Pop3Client.Stat, 'Stat'); 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
procedure TPOP3ExcercizerForm.ListAllButtonClick(Sender: TObject); 
begin 
    MsgNumEdit.Text := '0'; 
    Exec(Pop3Client.List, 'List All'); 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
procedure TPOP3ExcercizerForm.ListButtonClick(Sender: TObject); 
begin 
    Exec(Pop3Client.List, 'List'); 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
procedure TPOP3ExcercizerForm.DeleteButtonClick(Sender: TObject); 
begin 
    Exec(Pop3Client.Dele, 'Delete'); 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
procedure TPOP3ExcercizerForm.NoopButtonClick(Sender: TObject); 
begin 
    Exec(Pop3Client.Noop, 'Noop'); 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
procedure TPOP3ExcercizerForm.LastButtonClick(Sender: TObject); 
begin 
    Exec(Pop3Client.Last, 'Last'); 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
procedure TPOP3ExcercizerForm.ResetButtonClick(Sender: TObject); 
begin 
    Exec(Pop3Client.RSet, 'Rset'); 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
procedure TPOP3ExcercizerForm.TopButtonClick(Sender: TObject); 
begin 
    Exec(Pop3Client.Top, 'Top'); 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
procedure TPOP3ExcercizerForm.RpopButtonClick(Sender: TObject); 
begin 
    Exec(Pop3Client.RPop, 'Rpop'); 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
procedure TPOP3ExcercizerForm.UidlButtonClick(Sender: TObject); 
begin 
    Exec(Pop3Client.Uidl, 'Uidl'); 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
procedure TPOP3ExcercizerForm.ApopButtonClick(Sender: TObject); 
begin 
    Exec(Pop3Client.APop, 'Apop'); 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
{ This event handler is called when TPop3Client is about to receive a       } 
{ message. The MsgNum property gives the message number.                    } 
{ This event handler could be used to open the file used to store the msg.  } 
{ The file handle could be stored in the TPop3Client.Tag property to be     } 
{ easily retrieved by the OnMessageLine and OnMessageEnd event handlers.    } 
procedure TPOP3ExcercizerForm.Pop3ClientMessageBegin(Sender: TObject); 
begin 
    DisplayMemo.Lines.Add('*** Message ' + 
                          IntToStr((Sender as TPop3Cli).MsgNum) + 
                          ' begin ***'); 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
{ This event handler is called when TPop3Client has detected the end of a   } 
{ message, even if there is an error or exception, this event gets called.  } 
{ This event handler could be used to close the file used to store the msg. } 
procedure TPOP3ExcercizerForm.Pop3ClientMessageEnd(Sender: TObject); 
begin 
    DisplayMemo.Lines.Add('*** Message ' + 
                          IntToStr((Sender as TPop3Cli).MsgNum) + 
                          ' end ***'); 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
{ This event handler is called for each message line that TPop3Client is    } 
{ receiveing. This could be used to write the message lines to a file.      } 
procedure TPOP3ExcercizerForm.Pop3ClientMessageLine(Sender: TObject); 
begin 
    DisplayMemo.Lines.Add((Sender as TPop3Cli).LastResponse); 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
{ This event handler is called when TPop3Client is about to receive a       } 
{ list line. The MsgNum property gives the message number.                  } 
procedure TPOP3ExcercizerForm.Pop3ClientListBegin(Sender: TObject); 
begin 
    DisplayMemo.Lines.Add('*** List begin ***'); 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
{ This event handler is called when TPop3Client has received the last list  } 
{ line.                                                                     } 
procedure TPOP3ExcercizerForm.Pop3ClientListEnd(Sender: TObject); 
begin 
    DisplayMemo.Lines.Add('*** List End ***'); 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
{ This event handler is called for each list line received by TPop3Client.  } 
procedure TPOP3ExcercizerForm.Pop3ClientListLine(Sender: TObject); 
var 
    Buffer : String; 
begin 
    Buffer := 'MsgNum = ' + IntToStr((Sender as TPop3Cli).MsgNum) + ' ' + 
              'MsgSize = ' + IntToStr((Sender as TPop3Cli).MsgSize) + ' ' + 
              'Line = ''' + (Sender as TPop3Cli).LastResponse + ''''; 
    DisplayMemo.Lines.Add(Buffer); 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
procedure TPOP3ExcercizerForm.Pop3ClientUidlBegin(Sender: TObject); 
begin 
    DisplayMemo.Lines.Add('*** Uidl begin ***'); 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
procedure TPOP3ExcercizerForm.Pop3ClientUidlEnd(Sender: TObject); 
begin 
    DisplayMemo.Lines.Add('*** Uidl end ***'); 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
procedure TPOP3ExcercizerForm.Pop3ClientUidlLine(Sender: TObject); 
var 
    Buffer : String; 
begin 
    Buffer := 'MsgNum = ' + IntToStr((Sender as TPop3Cli).MsgNum) + ' ' + 
              'MsgUidl = ' + (Sender as TPop3Cli).MsgUidl + ''''; 
    DisplayMemo.Lines.Add(Buffer); 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
procedure TPOP3ExcercizerForm.MessageBegin(Sender: TObject); 
begin 
    MessageForm.Caption := 'Message ' + 
                           IntToStr((Sender as TPop3Cli).MsgNum); 
    MessageForm.Show; 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
procedure TPOP3ExcercizerForm.MessageLine(Sender: TObject); 
begin 
    MessageForm.DisplayMemo.Lines.Add((Sender as TPop3Cli).LastResponse); 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
procedure TPOP3ExcercizerForm.NextButtonClick(Sender: TObject); 
begin 
    MessageForm.DisplayMemo.Clear; 
    MessageForm.Caption       := 'Message'; 
    Pop3Client.OnMessageBegin := MessageBegin; 
    Pop3Client.OnMessageEnd   := nil; 
    Pop3Client.OnMessageLine  := MessageLine; 
    Pop3Client.OnRequestDone  := NextMessageRequestDone; 
    Pop3Client.MsgNum         := StrToInt(MsgNumEdit.Text); 
    Pop3Client.Retr; 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
procedure TPOP3ExcercizerForm.NextMessageRequestDone( 
    Sender: TObject; 
    RqType: TPop3Request; Error: Word); 
begin 
    if Error <> 0 then 
        Exit; 
 
    MsgNumEdit.Text   := IntToStr(StrToInt(MsgNumEdit.Text) + 1); 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
procedure TPOP3ExcercizerForm.GetAllMessageLine(Sender: TObject); 
begin 
    Writeln(FFile, (Sender as TPop3Cli).LastResponse); 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
{ The procedure here after will start an event chain that will eventually   } 
{ download all messages for the POP3 server. We cannot simply loop because  } 
{ the POP3 compomnet is asynchronous: it will not wait for operation done   } 
{ before returning. We must "chain" operations one after the other using    } 
{ the OnRequestDone event handler. We use the variable FGetAllState to keep } 
{ track of where we are.                                                    } 
{ To get all messages, we must first call Stat to know how many messages    } 
{ are on the server, then for each message we call Uidl to get a unique     } 
{ identifier for each message to build a file name and know if we already   } 
{ have a message, then we retrieve the message, then we increment the       } 
{ message number and continue until the number of messages is reached.      } 
{ We should start a TTimer to handle timeout...                             } 
procedure TPOP3ExcercizerForm.GetAllButtonClick(Sender: TObject); 
var 
    IniFile : TIniFile; 
begin 
    { Get path from INI file } 
    IniFile := TIniFile.Create(IniFileName); 
    FMsgPath    := IniFile.ReadString('Data', 'MsgPath', 
                                  ExtractFilePath(Application.ExeName)); 
    IniFile.Free; 
 
    { Be sure to have an ending backslash } 
    if (Length(FMsgPath) > 0) and (FMsgPath[Length(FMsgPath)] <> '\') then 
        FMsgPath := FMsgPath + '\'; 
 
    FGetAllState := 0; 
    FFileOpened  := FALSE; 
    Pop3Client.OnRequestDone  := GetAllRequestDone; 
    Pop3Client.OnMessageBegin := nil; 
    Pop3Client.OnMessageEnd   := nil; 
    Pop3Client.OnMessageLine  := GetAllMessageLine; 
    Pop3Client.Stat; 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
{ This event handler is called when a request related to GetAll is done.    } 
{ We check for errors and our state variable FGetAllState which tells us    } 
{ where we are (stat, uidl or retr which are the 4 commands we use.         } 
{ Note that we also could use Dele to remove the messages from the server.  } 
procedure TPOP3ExcercizerForm.GetAllRequestDone( 
    Sender: TObject; 
    RqType: TPop3Request; Error: Word); 
begin 
    if Error <> 0 then begin 
        if FFileOpened then begin 
            FFileOpened := FALSE; 
            CloseFile(FFile); 
        end; 
        DisplayMemo.Lines.Add('Error ' + Pop3Client.ErrorMessage); 
        Exit; 
    end; 
 
    try 
        case FGetAllState of 
        0: begin     { Comes from the Stat command } 
                if Pop3Client.MsgCount < 1 then begin 
                    DisplayMemo.Lines.Add('No message to download.'); 
                    Exit; 
                end; 
                Pop3Client.MsgNum := 1;    { Start with first message } 
                FGetAllState := 1; 
                Pop3Client.Uidl; 
           end; 
        1: begin     { Comes from the Uidl command } 
                FFileName := FMsgPath + 'Msg ' + Pop3Client.MsgUidl + '.txt'; 
                if FileExists(FFileName) then begin 
                    DisplayMemo.Lines.Add('Message ' + IntToStr(Pop3Client.MsgNum) + ' already here'); 
                    if Pop3Client.MsgNum >= Pop3Client.MsgCount then begin 
                        DisplayMemo.Lines.Add('Finished'); 
                        Exit; 
                    end; 
                    Pop3Client.MsgNum := Pop3Client.MsgNum + 1; 
                    FGetAllState := 1; 
                    Pop3Client.Uidl; 
                end 
                else begin 
                    DisplayMemo.Lines.Add('Message ' + IntToStr(Pop3Client.MsgNum)); 
                    AssignFile(FFile, FFileName); 
                    Rewrite(FFile); 
                    FFileOpened  := TRUE; 
                    FGetAllState := 2; 
                    Pop3Client.Retr; 
                end; 
           end; 
        2: begin     { Comes from the Retr command } 
                FFileOpened := FALSE; 
                CloseFile(FFile); 
                if Pop3Client.MsgNum >= Pop3Client.MsgCount then begin 
                    DisplayMemo.Lines.Add('Finished'); 
                    Exit; 
                end; 
                Pop3Client.MsgNum := Pop3Client.MsgNum + 1; 
                FGetAllState := 1; 
                Pop3Client.Uidl; 
           end; 
        else 
            DisplayMemo.Lines.Add('Invalid state'); 
            Exit; 
        end; 
    except 
        on E:Exception do begin 
            if FFileOpened then begin 
                FFileOpened := FALSE; 
                CloseFile(FFile); 
            end; 
            DisplayMemo.Lines.Add('Error: ' + E.Message); 
        end; 
    end; 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
procedure TPOP3ExcercizerForm.Pop3ClientRequestDone(Sender: TObject; 
  RqType: TPop3Request; Error: Word); 
begin 
    DisplayMemo.Lines.Add('Request Done Rq=' + IntToStr(Integer(RqType)) + 
                          ' Error=' + IntToStr(Error)); 
 
    if RqType = pop3Stat then begin 
        InfoLabel.Caption := 'Stat ok, ' + 
                             IntToStr(Pop3Client.MsgCount) + ' messages ' + 
                             IntToStr(Pop3Client.MsgSize) + ' bytes' 
    end 
    else if RqType = pop3List then begin 
        InfoLabel.Caption := 'List ok, ' + 
                             IntToStr(Pop3Client.MsgNum)  + ' message ' + 
                             IntToStr(Pop3Client.MsgSize) + ' bytes' 
    end 
    else if RqType = pop3Last then begin 
        InfoLabel.Caption := 'Last = ' + IntToStr(Pop3Client.MsgNum); 
    end; 
end; 
 
 
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} 
 
end.