Read any MAPI complient emails

Problem/Question/Abstract:

How can read emails from OutlookExpress, Outlook or Eudora from a Delphi program?

Answer:

We can read emails from any MAPI compliant email client using MAPI. The bad news is that we cannot read formatted email using simple MAPI, but only the plain text and attachments.

That�s because MAPI was created before HTML formatted emails were created. But MAPI can bevery useful anyway.

To run this program create a blank form (on IDE point to "File/Close all", then "File/New Application"), put a button on it, a Label (both on standard tab)and a RichEdit (on Win32 tab; I used a RichEdit because Memo can  only handle 32k of text).

unit Unit1;

{*****************************************************************
*       Simple MAPI sample                                      *
*       Source written by Rafael Cotta (rcotta.geo@yahoo.com)   *
*       July 26th, 2001                                         *
*****************************************************************}

// To run this sample, place on a blank form a TRichEdit, a TLabel
// and a TButton

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  StdCtrls, ComCtrls, MAPI;

type
  TForm1 = class(TForm)
    RichEdit1: TRichEdit;
    Button1: TButton;
    Label1: TLabel;
    procedure FormCreate(Sender: TObject);
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;
  hndMAPISession: Cardinal;
  v_CurrentMsgID: array[0..512] of char; // I�ll use long IDs here
implementation

{$R *.DFM}

procedure TForm1.FormCreate(Sender: TObject);
begin
  // Initializing components and variables
  v_CurrentMsgID[0] := #0;

  hndMAPISession := 0;

  Button1.Caption := 'Read Next';
  RichEdit1.Lines.Clear;
  Label1.Caption := 'Subject : ';

end;

procedure TForm1.Button1Click(Sender: TObject);
var
  dwRet: Cardinal;
  v_Out: array[0..512] of char;
  oMsg: PMapiMessage;
begin
  Label1.Caption := 'Retrieving... wait';

  if hndMAPISession = 0 then
  begin
    dwRet := MapiLogOn(
      Handle, // This window�s handle
      '', // If you want to use another profile that�s
      '', // not the default, set these two parameters
      MAPI_LOGON_UI, // Will prompt for logon if necessary
      0, // Reserve, must be 0
      @hndMAPISession);

    // An error occurred
    if (dwRet <> SUCCESS_SUCCESS) then
    begin
      MessageBox(Handle, PChar('Error ' + IntToHex(dwRet, 8) +
        ' while trying to logon'), PChar('Error'),
        MB_OK + MB_ICONERROR);
      Application.Terminate;
      Exit;
    end;
  end;

  dwRet := MapiFindNext(
    hndMAPISession,
    Handle,
    nil, // All messages
    @v_CurrentMsgID,
    MAPI_GUARANTEE_FIFO {sort by date; you can use "or MAPI_UNREAD_ONLY"},
    0,
    @v_Out // The messageId of message next to v_Current will be here
    );

  // Reached the end, so, going to first message
  if dwRet = MAPI_E_NO_MESSAGES then
  begin
    v_CurrentMsgID[0] := #0;

    MessageBox(Handle,
      PChar('Last message reached. Going to first one in InBox'),
      PChar('MAPI sample'),
      MB_OK + MB_ICONEXCLAMATION);

    dwRet := MapiFindNext(
      hndMAPISession,
      Handle,
      nil, // All messages
      @v_CurrentMsgID,
      MAPI_GUARANTEE_FIFO {sort by date; you can use "or MAPI_UNREAD_ONLY"},
      0,
      @v_Out // The messageId of message next to v_Current will be here
      );
  end;

  StrCopy(@v_CurrentMsgID, @v_Out);
  dwRet := MapiReadMail(
    hndMAPISession,
    Handle,
    @v_CurrentMsgID,
    MAPI_PEEK, // Won�t mark message as read
    0,
    oMsg
    );

  if dwRet = SUCCESS_SUCCESS then
  begin
    RichEdit1.SetTextBuf(oMsg.lpszNoteText);
    Label1.Caption := 'Subject : ' + StrPas(oMsg.lpszSubject);
  end;

  if Assigned(oMsg) then
    MapiFreeBuffer(oMsg);

end;

end.