ULogin unit;
    interface
    uses Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms, dialogs, StdCtrls, DB, ADODB;
    type
      TFrmLogin = class (TForm)
       Label1: TLabel;
       edusername: TEdit;
       Label2: TLabel;
       edpassword: TEdit;
       Button1: TButton;
       ADOQuery1: TADOQuery;
       ADOConnection1: TADOConnection;
       Button1Click procedure (Sender: TObject);
       FormCreate procedure (Sender: TObject);
      private
       {Private Declarations}
      public
       {Public Declarations} end;
    var FrmLogin: TFrmLogin;
    implementation uses
    / / XPMan for display form such as the button following the theme on windows
    / / Add to ULogin UHasilLogin unit by pressing Alt + F11, or with
    / / typed it

    XPMan, UHasilLogin;

    {$ R *. DFM}

    TFrmLogin.FormCreate procedure (Sender: TObject);
    var
    s: Char;
    alamatdb: WideString;
    begin

    / / Manipulation cursors crSQLWait order not to appear
    Screen.Cursors [crSQLWait]: = Screen.Cursors [crDefault];

    / / set the display form
    s: = '*';
    edusername.Text: ='';
    edpassword.PasswordChar: = s;
    edpassword.Text: ='';

    / / set the connection on ADOConnection
    / / This script allows you to manage database connections in applications
    / / in order to application can process database that has been selected in a computer
    / / anywhere without the need to have a path / address the same database.

    alamatdb: = ExtractFilePath (Application.ExeName) + 'data.mdb';
    with ADOConnection1 do begin
    Connected: = False;
    LoginPrompt: = False;
    Mode: = cmShareDenyNone;
    ConnectionString: = 'Provider = Microsoft.Jet.OLEDB.4.0; Data Source =' +
    alamatdb + '; persist Security Info = False';
    end;
    ADOConnection1.Connected: = True;
    end;

    TFrmLogin.Button1Click procedure (Sender: TObject);
    begin
        with ADOQuery1 do begin
          Close;
          SQL.Clear; / / clear command sql if there is.
          SQL.Add ('SELECT * FROM login WHERE username =' +
          QuotedStr (edusername.Text));
          Open;
        end; / / end with

        / / if not found then the data sought
        / / display message
        if ADOQuery1.RecordCount = 0 then
          Application.MessageBox ('Sorry, your username does not exist', 'Information',
          MB_OK or MB_ICONINFORMATION)
        else begin
          if ADOQuery1.FieldByName ('password'). AsString <> edpassword.Text then
            Application.MessageBox ('Make sure the correct username or password',
            'Error', MB_OK or MB_ICONERROR)
          else begin
             Hide;
             Form1.Show;
          end
        end;
    end;

    end.