void __fastcall TForm1::RichEdit1KeyDown(TObject *Sender, WORD &Key,
      TShiftState Shift)
{
  switch (Key)
  {
    case VK_RIGHT:
      ShowMessage("右鍵");
      break;        case VK_LEFT:
      ShowMessage("左鍵");
      break;        case VK_UP:
      ShowMessage("上鍵");
      break;        case VK_DOWN:
      ShowMessage("下鍵");
      break;        case VK_PRIOR:
      ShowMessage("Page Up 鍵");
      break;        case VK_NEXT:
      ShowMessage("Page Down 鍵");
      break;
  }
}