column chart data label, position and rotation, c#

Please note that this question is not x-axis label, rather it is about data label on the column of the chart.

The following  code does not rotate the data labels on the columns ( see line 59).

Question: How can I change  the code below to do the following:
      Part 1: Rotate the data labels by 90 degrees, and
      Part 2: To position the data label values inside (middle portion) of their respective columns.

Do I need to reduce font-size to be inside the column?

As it stands, the data labels are positioned at the tip of the columns.
protected void createMonthlyChartImagesSmall(string YYYY, int RegionID, string Region, int Metric_ID, int MedCtrID, string MedCenter, string chartImageName)
    {
        //  protected void createChart1()
        var filePathName = "~\\image\\" + chartImageName + "Small.png";
        if (!File.Exists(Server.MapPath(filePathName)))
        {
            // some dummy values...
            Session["Metric_ID"] = Metric_ID;
            Session["YYYY"] = YYYY;
            Session["MedCtr_ID"] = MedCtrID;

            SqlDataSource mySqlDataSource = new SqlDataSource();
            mySqlDataSource.ConnectionString = System.Configuration.ConfigurationManager.ConnectionStrings["ROD_July18ConnectionString"].ConnectionString;
            mySqlDataSource.SelectCommand = "spMonthlyChart";
            mySqlDataSource.SelectCommandType = SqlDataSourceCommandType.StoredProcedure;
            mySqlDataSource.SelectParameters.Add(new SessionParameter("Metric_ID", DbType.Int32, "Metric_ID"));
            mySqlDataSource.SelectParameters.Add(new SessionParameter("YYYY", DbType.String, "YYYY"));
            mySqlDataSource.SelectParameters.Add(new SessionParameter("MedCtr_ID", DbType.Int32, "MedCtr_ID"));

            Chart chart = new Chart();

            Series series = new Series("Default");
            series.ChartType = SeriesChartType.Column;
            chart.Series.Add(series);

            Series series2 = new Series("Default2");
            series2.ChartType = SeriesChartType.Line;
            series2.Color = System.Drawing.Color.Purple;// change color to put
            series2.BorderWidth = 1; // this is actually the line width...
            series2.BorderDashStyle = ChartDashStyle.Dot;
            //series2.IsValueShownAsLabel = true;

            chart.Series.Add(series2);

            ChartArea chartArea = new ChartArea();
            Axis yAxis = new Axis(chartArea, AxisName.Y);
            Axis xAxis = new Axis(chartArea, AxisName.X);

            series.XValueMember = "ColName"; // X
            series.YValueMembers = "ColValue"; // Y1
            series2.XValueMember = "ColName"; // X
            series2.YValueMembers = "Target"; // Y2
            chart.DataSource = mySqlDataSource;
            chart.DataBind();

            series2.IsValueShownAsLabel = false;
            series2.Points[0].IsValueShownAsLabel = true;

            chartArea.BackColor = Color.Transparent;// chart.ChartAreas.col
            chart.BackColor = Color.Transparent;
            chart.Series["Default"].Color = System.Drawing.Color.FromArgb(50, 140, 172, 0);
            chart.Series["Default"].Points[0].Color = System.Drawing.Color.FromArgb(50, 224, 0, 0);
            chart.Series["Default"].Points[chart.Series["Default"].Points.Count - 1].Color = System.Drawing.Color.FromArgb(30, 225, 128, 0);
            series.IsValueShownAsLabel = true; // 3 show value

            

            series.LabelForeColor = System.Drawing.Color.Black;
            series.LabelAngle = 90;
            //chart.ChartAreas[0].AxisX.LabelStyle.Angle = 90;
            chartArea.AxisX.MajorGrid.Enabled = false; // 1 don't show grid
            chartArea.AxisY.MajorGrid.Enabled = false;// 1 don't show grid
            chartArea.AxisY.LabelStyle.Enabled = false; // 2 remove y labels
            // 
            chartArea.AxisX.LabelStyle.Font = new Font("Arial", 8);
            chartArea.AxisX.LabelStyle.Angle = 90;
           // chartArea.AxisX.PositionToValue = midButtonsLabel;
//            protected void SummaryChart_Customize(object sender, EventArgs e)
//{
//    //hide label value if zero
//    foreach (System.Web.UI.DataVisualization.Charting.Series series in SummaryChart.Series)
//    {
//        foreach (System.Web.UI.DataVisualization.Charting.DataPoint point in series.Points)
//        {
//            if (point.YValues.Length > 0 && (double)point.YValues.GetValue(0) == 0)
//            {
//                point.IsValueShownAsLabel = false;
//            }
//        }
//    }
//}
            chartArea.AxisX.LabelStyle.ForeColor = System.Drawing.Color.White;
            chartArea.AxisX.LabelAutoFitStyle = 0;//??????? 
            //chart.BorderSkin.SkinStyle = BorderSkinStyle.FrameThin1;// add thin fram to border???????????
            chartArea.AxisY.MajorTickMark.Enabled = false; //5.remove tick marks and add border
            chartArea.BorderDashStyle = ChartDashStyle.Solid; //6. add border
            chartArea.BorderWidth = 1;
            chartArea.BorderColor = System.Drawing.Color.Black; //6. add border

            //chartArea.AxisX.IsLabelAutoFit = true;
            // chartArea.AxisX.LabelAutoFitStyle = LabelAutoFitStyles.LabelsAngleStep30;
            chartArea.AxisX.LabelStyle.Enabled = true;
            chartArea.AxisX.LabelStyle.Angle = -90; // 4 rotate x labels
            chartArea.AxisX.Interval = 1;// xhow all labels

            if (Metric_ID == 115 || Metric_ID == 113)
            {
                chart.Series["Default"].Color = System.Drawing.Color.FromArgb(255, 224, 0, 0);//light red;
                chart.Series["Default"].BackGradientStyle = GradientStyle.DiagonalLeft;
                chart.Series["Default"].BackSecondaryColor = System.Drawing.Color.FromArgb(255, 147, 0, 0);//dark red
            }
            else
            {
                chart.Series["Default"].Color = System.Drawing.Color.FromArgb(255, 152, 200, 0);//light green;
                chart.Series["Default"].BackGradientStyle = GradientStyle.DiagonalLeft;
                chart.Series["Default"].BackSecondaryColor = System.Drawing.Color.FromArgb(255, 129, 132, 0);//dark green
            }
            chart.Series["Default"].Points[0].Color = System.Drawing.Color.FromArgb(255, 255, 150, 0);//light orange ;//FromArgb(255, 224, 0, 0);//light Red;
            chart.Series["Default"].Points[0].BackGradientStyle = GradientStyle.DiagonalLeft;
            chart.Series["Default"].Points[0].BackSecondaryColor = System.Drawing.Color.FromArgb(255, 255, 105, 0);//Dark orange;//FromArgb(255, 147, 0, 0);//DarkRed;
            chart.Series["Default"].Points[chart.Series["Default"].Points.Count - 1].Color = System.Drawing.Color.FromArgb(255, 190, 124,207);//light purple;
            chart.Series["Default"].Points[chart.Series["Default"].Points.Count - 1].BackGradientStyle = GradientStyle.DiagonalLeft;
            chart.Series["Default"].Points[chart.Series["Default"].Points.Count - 1].BackSecondaryColor = System.Drawing.Color.FromArgb(255, 153,66,123);//dark purple
            //  series.LabelStyle.Font = new Font("Palatino Linotype", 12);

     //       chartArea.BackGradientStyle = GradientStyle.DiagonalLeft;
            chartArea.BackColor = System.Drawing.Color.White;// SlateGray;
     //       chartArea.BackSecondaryColor = System.Drawing.Color.White;
            // chartArea.Position.X = 0;
            //  chartArea.Position.Y = 0;

            series.Font = new Font("Arial", 8f);
            // chartArea.AxisX.Interval = 1;
  //          chart.Titles.Add(string.Format("{0}{1}{2} ", MedCenter, ", Metric " + Metric_ID, " - " + YYYY));
 //           chart.Titles[0].Alignment = ContentAlignment.TopLeft;
 //           chart.Titles[0].Font = new Font("Tahoma", 20f);
  //          chart.Titles[0].ForeColor = System.Drawing.Color.White;
            //chart.Titles[0].Font=Bold;

            chart.Width = new Unit(214, UnitType.Pixel);
            chart.Height = new Unit(158, UnitType.Pixel);
            chart.ChartAreas.Add(chartArea);
            string filename = "C:\\Users\\Mike\\Documents\\_smc\\__CS37\\MasterPageTestJul25\\image\\" + chartImageName + "Small.png";
            chart.SaveImage(filename, ChartImageFormat.Png);

        }
    }

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LVL 34
Mike EghtebasDatabase and Application DeveloperAsked:
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Robert SchuttSoftware EngineerCommented:
Could it be that this is not possible? I looked into CustomProperties and TextAnnotations but couldn't find a solution.

Here is a solution using the PostPaint event; after creating the chart object (line 20) add this:
chart.PostPaint += new EventHandler<ChartPaintEventArgs>(chart_PostPaint);

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Then add this event handler:
        void chart_PostPaint(object sender, ChartPaintEventArgs e) {

            Font fnt = new Font("Arial", 8);
            StringFormat sf = new StringFormat(StringFormatFlags.DirectionVertical);
            sf.Alignment = StringAlignment.Center;
            sf.LineAlignment = StringAlignment.Center;

            if (e.ChartElement.GetType().Name.Equals("Series")) {
                Series s = (Series)e.ChartElement;
                if (s.Name == "Default") {
                    for (int p = 0; p < s.Points.Count; p++) {
                        PointF p1 = new PointF(
                            (float)e.ChartGraphics.GetPositionFromAxis(s.ChartArea, AxisName.X, (e.Chart.ChartAreas[s.ChartArea].AxisX.Maximum - e.Chart.ChartAreas[s.ChartArea].AxisX.Minimum - 1) * (p + 1) / (s.Points.Count)),
                            (float)e.ChartGraphics.GetPositionFromAxis(s.ChartArea, AxisName.Y, s.Points[p].YValues[0] / 2)
                        );
                        PointF p1a = e.ChartGraphics.GetAbsolutePoint(p1);
                        e.ChartGraphics.Graphics.DrawString(s.Points[p].YValues[0].ToString(), fnt, Brushes.Black, p1a, sf);
                    }
                }
            }
        }

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0
Mike EghtebasDatabase and Application DeveloperAuthor Commented:
Robert,

You are amazing. You make it all possible.

The data points show up rotated (I suppose by 90 degrees) in the middle of the columns. I tried to locate the angle value and change it to -90 (for a better readability) but I didn't see any angle entry.

Question: How can I rotate the values (now reads top-to-bottom) to read Bottpm-to-top?

Thank you,

Mike
0
Robert SchuttSoftware EngineerCommented:
Hmm good one. The rotation in this case is done by StringFormatFlags.DirectionVertical, but I don't see an obvious way to make it go from bottom to top. I did find some examples to draw a string rotated the other way with some more customization but the result was unreadable so I'm trying another option, will need some time though.
0
Robert SchuttSoftware EngineerCommented:
In the end the solution was pretty simple but initially I had forgotten to take out the StringFormatFlags.DirectionVertical so when you rotate that it's back to normal... here's the code, you may wanna play around with font size and move a pixel or 2 here and there:
        void chart_PostPaint(object sender, ChartPaintEventArgs e) {

            Font fnt = new Font("Arial", 8);
            StringFormat sf = new StringFormat();
            sf.Alignment = StringAlignment.Center;
            sf.LineAlignment = StringAlignment.Center;

            if (e.ChartElement.GetType().Name.Equals("Series")) {
                Series s = (Series)e.ChartElement;
                if (s.Name == "Default") {
                    for (int p = 0; p < s.Points.Count; p++) {
                        PointF p1 = new PointF(
                            (float)e.ChartGraphics.GetPositionFromAxis(s.ChartArea, AxisName.X, (e.Chart.ChartAreas[s.ChartArea].AxisX.Maximum - e.Chart.ChartAreas[s.ChartArea].AxisX.Minimum - 1) * (p + 1) / (s.Points.Count)),
                            (float)e.ChartGraphics.GetPositionFromAxis(s.ChartArea, AxisName.Y, s.Points[p].YValues[0] / 2)
                        );
                        PointF p1a = e.ChartGraphics.GetAbsolutePoint(p1);
                        // note the order: first move center to actual position, then rotate, then draw string at (0, 0)
                        e.ChartGraphics.Graphics.TranslateTransform(p1a.X, p1a.Y);
                        e.ChartGraphics.Graphics.RotateTransform(-90);
                        e.ChartGraphics.Graphics.DrawString(s.Points[p].YValues[0].ToString(), fnt, Brushes.Black, 0, 0, sf);
                        e.ChartGraphics.Graphics.ResetTransform();
                    }
                }
            }
        }

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