public void getcartesianChart()
        {
            ChartValues <double> AC_Values     = new ChartValues <double>();
            ChartValues <double> Submit_Values = new ChartValues <double>();
            DateTime             NOW           = DateTime.Now;
            DateTime             last_time;

            if (DateTime.Compare(NOW, OperateForm.end_time) > 0)
            {
                NOW = OperateForm.end_time;
            }
            if (DateTime.Compare(NOW, OperateForm.start_time) < 0)
            {
                NOW = OperateForm.start_time;
            }
            last_time = NOW;

            TimeSpan timeSpan = NOW - OperateForm.start_time;
            DateTime st       = OperateForm.start_time;
            DateTime nx       = new DateTime();
            int      len      = (int)double.Parse(timeSpan.TotalMinutes.ToString());

            len = Math.Min(300, len);
            len = Math.Max(0, len);
            AC_Values.Add(0);
            Submit_Values.Add(0);
            for (int i = 0; i < len; i += 1)
            {
                nx = st.AddMinutes(1);
                try
                {
                    AC_Values.Add(double.Parse(DBTool.getTotSubmitByStEdAndResult(st.ToString(), nx.ToString(), 4).ToString()));
                    Submit_Values.Add(double.Parse(DBTool.getTotSubmitByStEd(st.ToString(), nx.ToString()).ToString()));
                }
                catch (Exception ex)
                {
                    print("网络连接中断!");
                    Application.Exit();
                }
                st = nx;
            }

            cartesianChart1.Series.Clear();
            cartesianChart1.Series.Add(new LineSeries
            {
                Values            = AC_Values,
                StrokeThickness   = 2,
                StrokeDashArray   = new System.Windows.Media.DoubleCollection(new double[] { 2 }),
                Stroke            = new System.Windows.Media.SolidColorBrush(System.Windows.Media.Color.FromRgb(107, 185, 69)),
                Fill              = System.Windows.Media.Brushes.Transparent,
                LineSmoothness    = 0,
                PointGeometrySize = 1,
                Title             = "AC",
            });

            cartesianChart1.Series.Add(new LineSeries
            {
                Values            = Submit_Values,
                StrokeThickness   = 2,
                Stroke            = new System.Windows.Media.SolidColorBrush(System.Windows.Media.Color.FromRgb(28, 142, 196)),
                Fill              = System.Windows.Media.Brushes.Transparent,
                LineSmoothness    = 1,
                PointGeometrySize = 1,
                PointForeground   =
                    new System.Windows.Media.SolidColorBrush(System.Windows.Media.Color.FromRgb(34, 46, 49)),
                Title = "Submit"
            });

            cartesianChart1.Background = new System.Windows.Media.SolidColorBrush(System.Windows.Media.Color.FromRgb(34, 46, 49));

            cartesianChart1.AxisX.Add(new Axis
            {
                IsMerged  = true,
                Separator = new Separator
                {
                    Step            = 20,
                    StrokeThickness = 1,
                    StrokeDashArray = new System.Windows.Media.DoubleCollection(new double[] { 2 }),
                    Stroke          = new System.Windows.Media.SolidColorBrush(System.Windows.Media.Color.FromRgb(64, 79, 86))
                }
            });

            cartesianChart1.AxisY.Add(new Axis
            {
                IsMerged  = true,
                Separator = new Separator
                {
                    StrokeThickness = 1.5,
                    StrokeDashArray = new System.Windows.Media.DoubleCollection(new double[] { 4 }),
                    Stroke          = new System.Windows.Media.SolidColorBrush(System.Windows.Media.Color.FromRgb(64, 79, 86))
                }
            });
        }