Step to UEFI (186）NT32Pkg 下面的按键

  //
  // Initialize Simple Text In protoocol
  //
  Private->SimpleTextIn.Reset         = WinNtGopSimpleTextInReset;
  Private->SimpleTextIn.ReadKeyStroke = WinNtGopSimpleTextInReadKeyStroke;

  Status = gBS->CreateEvent (
                  EVT_NOTIFY_WAIT,
                  TPL_NOTIFY,
                  WinNtGopSimpleTextInWaitForKey,
                  Private,
                  &Private->SimpleTextIn.WaitForKey
                  );


  Private->SimpleTextInEx.Reset               = WinNtGopSimpleTextInExResetEx;
  Private->SimpleTextInEx.ReadKeyStrokeEx     = WinNtGopSimpleTextInExReadKeyStrokeEx;
  Private->SimpleTextInEx.SetState            = WinNtGopSimpleTextInExSetState;
  Private->SimpleTextInEx.RegisterKeyNotify   = WinNtGopSimpleTextInExRegisterKeyNotify;
  Private->SimpleTextInEx.UnregisterKeyNotify = WinNtGopSimpleTextInExUnregisterKeyNotify;

EFI_STATUS
GopPrivateReadKeyStrokeWorker (
  IN GOP_PRIVATE_DATA                   *Private,
  OUT EFI_KEY_DATA                      *KeyData
  )
/*++

  Routine Description:
    Reads the next keystroke from the input device. The WaitForKey Event can
    be used to test for existance of a keystroke via WaitForEvent () call.

  Arguments:
    Private    - The private structure of WinNt Gop device.
    KeyData    - A pointer to a buffer that is filled in with the keystroke
                 state data for the key that was pressed.

  Returns:
    EFI_SUCCESS           - The keystroke information was returned.
    EFI_NOT_READY         - There was no keystroke data availiable.
    EFI_DEVICE_ERROR      - The keystroke information was not returned due to
                            hardware errors.
    EFI_INVALID_PARAMETER - KeyData is NULL.

--*/
{
  EFI_STATUS                      Status;
  EFI_TPL                         OldTpl;

  if (KeyData == NULL) {
    return EFI_INVALID_PARAMETER;
  }

  //
  // Enter critical section
  //
  OldTpl  = gBS->RaiseTPL (TPL_NOTIFY);

  //
  // Call hot key callback before telling caller there is a key available
  //
  WinNtGopSimpleTextInTimerHandler (NULL, Private);

  ZeroMem (&KeyData->Key, sizeof (KeyData->Key));
  InitializeKeyState (Private, &KeyData->KeyState);

  Status  = GopPrivateCheckQ (&Private->QueueForRead);
  if (!EFI_ERROR (Status)) {
    //
    // If a Key press exists try and read it.
    //
    Status = GopPrivateDeleteQ (Private, &Private->QueueForRead, KeyData);
    if (!EFI_ERROR (Status)) {
      //
      // If partial keystroke is not enabled, check whether it is value key. If not return
      // EFI_NOT_READY.
      //
      if (!Private->IsPartialKeySupport) {
        if (KeyData->Key.ScanCode == SCAN_NULL && KeyData->Key.UnicodeChar == CHAR_NULL) {
          Status = EFI_NOT_READY;
        }
      }
    }
  }

  //
  // Leave critical section and return
  //
  gBS->RestoreTPL (OldTpl);

  return Status;

}

EFI_STATUS
GopPrivateAddKey (
  IN  GOP_PRIVATE_DATA    *Private,
  IN  EFI_INPUT_KEY       Key
  );

  case WM_CHAR: 
 
    //
    // The ESC key also generate WM_CHAR.
    //
    if (wParam == 0x1B) {
	    return 0;
    }    

    if (AltIsPress == TRUE) {
      //
      // If AltIsPress is true that means the Alt key is pressed.
      //
      Private->LeftAlt = TRUE;
    }
    for (Index = 0; Index < (lParam & 0xffff); Index++) {
      if (wParam != 0) {
        Key.UnicodeChar = (CHAR16) wParam;
        Key.ScanCode    = SCAN_NULL;     
        GopPrivateAddKey (Private, Key);    
      }
    }
    if (AltIsPress == TRUE) {
      //
      // When Alt is released there is no windoes message, so 
      // clean it after using it.
      //
      Private->LeftAlt  = FALSE;
      Private->RightAlt = FALSE;
    }
    DEBUG ((EFI_D_INFO, "Key [%X] [%X]\n",Key.ScanCode,Key.UnicodeChar)); //LABZ_DEBUG
 
return 0;