I have 3 columns datatable; I want to show values of INST_ID and Legends on my chart.

My problem is, INST_ID can be vary. It may have 5 different INST_IDs.

How can I show all series belongs to INST_ID and legends?

Here is the current Result

Here is the code that I generate for the Ultra Data Chart

private void Form1_Load(object sender, EventArgs e)
    { 
        dtLineTest.Columns.Add("SAMPLE_TIME",typeof(DateTime));
        dtLineTest.Columns.Add("INST_ID", typeof(Int32));
        dtLineTest.Columns.Add("VALUE", typeof(Int32));

        dtLineTest.Rows.Add(DateTime.Now,1,14);
        dtLineTest.Rows.Add(DateTime.Now.AddMinutes(-1), 1, 18);
        dtLineTest.Rows.Add(DateTime.Now.AddMinutes(-2), 1, 11);
        dtLineTest.Rows.Add(DateTime.Now.AddMinutes(-3), 1, 7);
        dtLineTest.Rows.Add(DateTime.Now.AddMinutes(-4), 1, 21);

        dtLineTest.Rows.Add(DateTime.Now, 2, 16);
        dtLineTest.Rows.Add(DateTime.Now.AddMinutes(-1), 2, 3);
        dtLineTest.Rows.Add(DateTime.Now.AddMinutes(-2), 2, 5);
        dtLineTest.Rows.Add(DateTime.Now.AddMinutes(-3), 2, 12);
        dtLineTest.Rows.Add(DateTime.Now.AddMinutes(-4), 2, 13);

        var xAxis = new CategoryXAxis();
        var yAxis = new NumericYAxis();

        xAxis.DataSource = dtLineTest;
        xAxis.Label = "SAMPLE_TIME";

        var legend = new UltraLegend();
        var lineSeries = new LineSeries();
        lineSeries.DataSource = dtLineTest;
        lineSeries.ValueMemberPath = "VALUE";
        lineSeries.Title = "INST_ID";
        lineSeries.XAxis = xAxis;
        lineSeries.YAxis = yAxis;
        lineSeries.Legend = legend;

        ultraDataChart1.Axes.Add(xAxis);
        ultraDataChart1.Axes.Add(yAxis);
        ultraDataChart1.Series.Add(lineSeries);
    }

CodePudding user response：

To show several lines in the chart you need to add several lineSeries to the chart. In your case you can group the data in the table by INST_ID column and create a lineSeries for each group. Something like this:

var groupedData = dtLineTest.AsEnumerable().GroupBy(g => g["INST_ID"]);
foreach (var group in groupedData)
{
    var dt = new DataTable();
    dt.Columns.Add("SAMPLE_TIME", typeof(DateTime));
    dt.Columns.Add("INST_ID", typeof(Int32));
    dt.Columns.Add("VALUE", typeof(Int32));
    foreach (var row in group)
    {
        dt.Rows.Add(row.ItemArray);
    }
    var legend = new UltraLegend();
    var lineSeries = new LineSeries();
    lineSeries.DataSource = dt;
    lineSeries.ValueMemberPath = "VALUE";
    lineSeries.Title = "INST_ID";
    lineSeries.XAxis = xAxis;
    lineSeries.YAxis = yAxis;
    lineSeries.Legend = legend;
    ultraDataChart1.Series.Add(lineSeries);
}

Note: it will be much easier if you have separate table for each series beforehand.