Forms Delphi

const InputBoxMessage = WM_USER + 200;
type
TForm1 = class(TForm)
Edit1: TEdit;
Button1: TButton;
procedure Button1Click(Sender: TObject);
private
{ Private declarations }
procedure InputBoxSetPasswordChar(var Msg: TMessage); message InputBoxMessage;
public
{ Public declarations }
end;
var
Form1: TForm1;
implementation
{$R *.DFM}
{ TForm1 }
procedure TForm1.InputBoxSetPasswordChar(var Msg: TMessage);
var
hInputForm, hEdit, hButton: HWND;
begin
hInputForm := Screen.Forms[0].Handle;
if (hInputForm <> 0) then
begin
hEdit := FindWindowEx(hInputForm, 0, 'TEdit', nil);
SendMessage(hEdit, EM_SETPASSWORDCHAR, Ord('*'), 0);
end;
end;
procedure TForm1.Button1Click(Sender: TObject);
var
InputString: string;
begin
PostMessage(Handle, InputBoxMessage, 0, 0);
InputString := InputBox('Input Box', 'Please Enter a Password', '');
Edit1.Text := InputString;
end;