Читаем файл Access используя ADO

// Читаем файл (любой версии) 
// Проверяем что это ACCESS MDB 
// Нужны компаненты: 
// TADOtable,TDataSource,TOpenDialog,TDBGrid,TBitBtn. 
unit
 uMain; 

interface
 

uses
 
Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs, 
Db, DBTables, ADODB, Grids, DBGrids, ExtCtrls, DBCtrls, StdCtrls, Buttons; 

type
 
  TfrmMain = class
(TForm) 
    DSUsers: TDataSource; 
    DBGridUsers: TDBGrid; 
    BitBtn1: TBitBtn; 
    OpenDialog1: TOpenDialog; 
    TUsers: TADOTable; 
    procedure
 FormCreate(Sender: TObject); 
    procedure
 ValidateAccessDB; 
    function
 CheckIfAccessDB(lDBPathName: string
): boolean; 
  private
 
    { Private declarations } 
  public
 
    { Public declarations } 
  end
; 

var
 
  frmMain: TfrmMain; 
const
 
  DBNAME = 'ADODemo.MDB'; 
  DBPASSWORD = '123'; // Access DB Password Protected 

implementation
 

{$R *.DFM} 

procedure
 TfrmMain.FormCreate(Sender: TObject); 
begin
 
  validateAccessDB; 
end
; 

procedure
 TfrmMain.ValidateAccessDB; 
var
 
  lDBpathName : String
; 
  lDBcheck : boolean; 
begin
 
  if
 FileExists(ExtractFileDir(Application.ExeName) + '' + DBNAME) then
 
    lDBPathName := ExtractFileDir(Application.ExeName) + '' + DBNAME 
  else
 if
 OpenDialog1.Execute then
 
    // Set the OpenDialog Filter for ADOdemo.mdb only 
    lDBPathName := OpenDialog1.FileName; 

  lDBCheck := False
; 
  if
 Trim(lDBPathName) <> '' then
 
    lDBCheck := CheckIfAccessDB(lDBPathName); 

  if
 lDBCheck = True
 then
 
  begin
 
    // ADO Connection String to the MS-ACCESS DB 
    TUsers.ConnectionString := 
      'Provider=Microsoft.Jet.OLEDB.4.0;' + 
      'Data Source=' + lDBPathName + ';' + 
      'Persist Security Info=False;' + 
      'Jet OLEDB:Database Password=' + DBPASSWORD; 
    TUsers.TableName := 'Users'; 
    TUsers.Active := True
; 
  end
 
  else
 
    frmMain.Free; 
end
; 

// Check if it is a valid ACCESS DB File Before opening it. 

function
 TfrmMain.CheckIfAccessDB(lDBPathName: string
): Boolean; 
var
 
  UnTypedFile: file
 of
 byte; 
  Buffer: array
[0..19] of
 byte; 
  NumRecsRead: Integer; 
  i: Integer; 
  MyString: string
; 
begin
 
  AssignFile(UnTypedFile, lDBPathName); 
  reset(UnTypedFile); 
  BlockRead(UnTypedFile, Buffer, High(Buffer), NumRecsRead); 
  CloseFile(UnTypedFile); 
  for
 i := 1 to
 High(Buffer) do
 
    MyString := MyString + Trim(Chr(Ord(Buffer[i]))); 
  Result := False
; 
  if
 Mystring = 'StandardJetDB' then
 
    Result := True
; 
  if
 Result = False
 then
 
    MessageDlg('Invalid Access Database', mtInformation, [mbOK], 0); 
end
; 
end
.

Другое по теме:

• Записываем в Access используя ADO
• Использование таблиц Access
• Использование таблиц Access2