delphi
//Determina, si el campo TEdit tiene Caracteres de Contraseña function HasPasswordChar(AHandle: HWND): Boolean; var dwStyle: DWORD; begin dwStyle := GetWindowLong(AHandle, GWL_STYLE); Result := (dwStyle and ES_PASSWORD) = ES_PASSWORD; end; // Define los Caracteres al TEdit procedure SetPasswordChar(AHandle: HWND; Value: Char); var S: String; len: Integer; begin len := Sendmessage(AHandle, WM_GETTEXTLENGTH, 0, 0); SetLength(S, len); SendMessage(AHandle, WM_GETTEXT, len+1, lparam(@S[1])); SendMessage(AHandle, EM_SETPASSWORDCHAR, Ord(Value), 0); SendMessage(AHandle, WM_SETTEXT, 0, Integer(PChar(S))); end; // Cancela y Revela el Texto detras. procedure CancelPasswordChar(AHandle: HWND); var S: string; len: Integer; begin len := SendMessage(AHandle, WM_GETTEXTLENGTH, 0, 0); SetLength(S, len); SendMessage(AHandle, WM_GETTEXT, len + 1, lParam(@S[1])); SendMessage(AHandle, EM_SETPASSWORDCHAR, 0, 0); SendMessage(AHandle, WM_SETTEXT, 0, Integer(PChar(S))); end;
Ejemplo de Uso:
delphi
procedure TForm1.Button1Click(Sender: TObject); var wnd: HWND; begin wnd := FindWindowEx(GetForeGroundWindow, 0, 'TEdit', nil); if wnd <> 0 then SetPasswordChar(wnd,'*'); end;
Saludos!