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DRKB - это самая большая и удобная в использовании база знаний по Дельфи в рунете, составленная Виталием Невзоровым

Как использовать свой диалог ввода пароля BDE?

01.01.2007
//  .....
//  .....
  public
    { Public declarations }
    procedure Password(Sender: TObject; var Continue: Boolean);
//    ...
  end;
 
var
  FormMain: TFormMain;
 
implementation
{$R *.dfm}
 
procedure TFormMain.Password(Sender: TObject; var Continue: Boolean);
var
  Passwd: String[15];
begin
  Passwd := '';
 
  FormPasswd := TFormPasswd.Create(Application);  // Creating dialog
  try
    if (FormPasswd.ShowModal = ID_OK) then begin  // If OK is pressed then get password from edit "edPassword"
      Passwd := FormPasswd.edPasswd.Text
    end
      else begin                                  // If Cancel is pressed then terminate application
        Application.ShowMainForm := False;
        Application.Terminate;
        Exit;
      end;
  finally
    FormPasswd.Free;                              // finally free password form
  end;
 
  Continue := (Passwd > '');
  Session.AddPassword(Passwd);                    // Add password typed to session
end;
 
procedure TFormMain.FormCreate(Sender: TObject);
begin
  ClientDatabase.Session.RemoveAllPasswords;  // Remove all typed passwords from session, so user need type password again in app start
//  Undocument next row in debug mode. This is for debugging and testing only, so we don't need typing password again and again ...
//  ClientDatabase.Session.AddPassword('YOUR-PASSWORD');
  ClientDatabase.Session.OnPassword := Password;  // Set OnPassword Event
end;

Взято с https://delphiworld.narod.ru