/// <summary>
        /// <para>******************</para>
        /// Watch Gray Level (灰階
        /// <para>******************</para>
        /// </summary>
        /// <param name="viewPort"></param>
        private void setWatchGrayLevel(HWindowControl viewPort, HWndCtrl viewController)
        {
            if (viewPort != null)
            {
                viewPort.HMouseMove += (sender, e) =>
                {
                    if (viewController == null) return;
                    var currImage = viewController.GetLastHImage();
                    if (currImage != null)
                    {
                        var row = (int)Math.Round(e.Y, 0);
                        var col = (int)Math.Round(e.X, 0);
                        try
                        {
                            HTuple width, height, grayval;
                            currImage.GetImageSize(out width, out height);
                            var mouseInImage = (row <= height.I && col <= width.I && row >= 0 && col >= 0);
                            if (mouseInImage)
                            {
                                HOperatorSet.GetGrayval(currImage, row, col, out grayval);
                                var dispText = grayval.I.ToString();
                                SetStatus(SystemStatusType.GrayLevel, dispText);
                            }
                        }
                        catch (Exception ex)
                        {
                            AddMessage(ex.Message);
                        }
                    }

                };
            }
        }