有个有关问题，求指导

  public void GetControl(Canvas can)        {            try            {                GeometryGroup gg = new GeometryGroup();                PathGeometry pg = new PathGeometry();                PathFigure pf = new PathFigure();                if (!String.IsNullOrEmpty(MaxConwidth.Text) && !String.IsNullOrEmpty(MinConwidth.Text) && !String.IsNullOrEmpty(MaxConHeight.Text) && !String.IsNullOrEmpty(MinConHeight.Text) && !String.IsNullOrEmpty(Diameter.Text) && !String.IsNullOrEmpty(WidthInterval.Text) && !String.IsNullOrEmpty(HeightInterval.Text) && !String.IsNullOrEmpty(Interval.Text) && !String.IsNullOrEmpty(reCloumns.Text) && !String.IsNullOrEmpty(reRows.Text) && !String.IsNullOrEmpty(Conthickness.Text) && !String.IsNullOrEmpty(Pointthickness.Text))                {                    //宽度                    double width = double.Parse(MaxConwidth.Text) * 10;                    //高度                    double height = double.Parse(MaxConHeight.Text) * 10;                    //直径                    double diameter = double.Parse(Diameter.Text) * 10;                    double widthinterval = double.Parse(WidthInterval.Text) * 10;                    double heightinterval = double.Parse(HeightInterval.Text) * 10;                    //间距                    double interval = double.Parse(Interval.Text) * 10;                    //第一个孔的坐标                    double Y = (height - heightinterval) / 2;                    double X = (width - widthinterval) / 2;                    for (int j = 0; j < int.Parse(reCloumns.Text); j++)                    {                        for (int i = 0; i < int.Parse(reRows.Text); i++)                        {                            EllipseGeometry eg = new EllipseGeometry();                            //中心点                            eg.Center = new Point(X + i * interval, Y + j * interval);                            eg.RadiusX = diameter / 2;                            eg.RadiusY = diameter / 2;                            gg.Children.Add(eg);                        }                    }                    reCounts.Text = (int.Parse(reCloumns.Text) * int.Parse(reRows.Text)).ToString();                    pf.StartPoint = new Point(0, 0);                    pf.Segments.Add(new PolyLineSegment(new Point[3] { new Point(width, 0), new Point(width, height), new Point(0, height) }, true));                    pg.Figures.Add(pf);                    gg.Children.Add(pg);                    can.Clip = gg;                    double w = X + interval * (int.Parse(reRows.Text) - 1) + diameter / 2;                    double r = Y + interval * (int.Parse(reCloumns.Text) - 1) + diameter / 2;                    if (w > width || r > height || (X - diameter / 2) < 0 || (Y - diameter / 2) < 0)                    {                        can.Background = Brushes.Red;                    }                    else                    {                        can.Background = new SolidColorBrush(Color.FromArgb(62, 00, 00, 00));                    }                }            }            catch (Exception)            {            }        }