how to use DataBindTable method to populate X-values to mutiple series?

Question

User537440814 posted

Hello friends,

I am using DataBindTable() to bind a table to a  chart. There are several float type columns for Y values and a date type column for the X value of all other columns. But only the first series(i.e. series of index 0) got the right x values, the x values of other series seems to be set to the same random series that I don't know where it come from. I have also tried to assign each series mannually but got the same result. I have attached my two failed function and the result chart images below, could someone help me get out of this? Thanks!

chart image(only one series is enable in each image):

                             image of first series                                                                     image of second series

function 1:  use DataBindTable()

private void RequestSensorData1()
    {

        string ConStr = "connectio string omitted...";
        string CmdStr = "command string omitted...";
        DataTable ds = new DataTable();
        try
        {
            myConn.Open();
            myConn = new MySqlConnection(ConStr);
            myCmd = new MySqlCommand(CmdStr, myConn);
            MySqlDataAdapter dataAdapter = new MySqlDataAdapter(myCmd);
            dataAdapter.Fill(ds);
            MyChart.DataBindTable(ds.AsDataView(), "time column");
        }
        catch
        {

        }
        finally
        {
            myConn.Close();
        }
    }

function 2:  set each series mannually

private void RequestSensorData()
    {

        string ConStr = "connectio string omitted...";
        string CmdStr = "command string omitted...";
        MySqlConnection myConn = new MySqlConnection(ConStr);
        try
        {
            myConn.Open();
            MySqlCommand myCmd = new MySqlCommand(CmdStr, myConn);
            MySqlDataReader myReader = myCmd.ExecuteReader();
            if (myReader.Read())
            {
                Charts[FocusedChart].DataSource = myReader;
                //Charts[FocusedChart].Series.Clear();
                MyChart.Series["Series1"].XValueMember = "time Column";
                MyChart.Series["Series1"].YValueMembers = "Y Column1";
                MyChart.Series["Series2"].XValueMember = "time  Column";
                MyChart.Series["Series2"].YValueMembers = "Y Column2";
                MyChart.Series["Series3"].XValueMember = "time  Column";
                MyChart.Series["Series3"].YValueMembers = "Y Column3";
                //...
                MyChart.DataBind();
                myReader.Close();
            }
        }
        catch
        {

        }
        finally
        {
            myConn.Close();
        }
    }

Answer 1

User283571144 posted

Hi Zachary.Chen,

But only the first series(i.e. series of index 0) got the right x values, the x values of other series seems to be set to the same random series that I don't know where it come from.

According to your description, I had written a demo on my computer.

I find if I don't set Series.XValueType to ChartValueType.DateTime,  it will show the result as image 2 shows.

So I suggest you change your codes and set  Series.XValueType to each series.

More details about my test demo, you could refer to follow codes:

Chart:

   <asp:Chart ID="Chart1" runat="server" Width="951px">
            <Series>
                <asp:Series Name="Series1"></asp:Series>
            </Series>
               <Series>
                <asp:Series Name="Series2"></asp:Series>
            </Series>
            <ChartAreas>
                <asp:ChartArea Name="ChartArea1"></asp:ChartArea>
            </ChartAreas>
              <ChartAreas>
                <asp:ChartArea Name="ChartArea2"></asp:ChartArea>
            </ChartAreas>
        </asp:Chart>

Code-behind：

protected void Page_Load(object sender, EventArgs e)
        {
            DataTable dt = new DataTable();
            dt.Columns.Add("weightNow", typeof(Int32));
            dt.Columns.Add("weightNow2", typeof(Int32));
            dt.Columns.Add("dateNow", typeof(DateTime));
            DateTime departure = new DateTime(2016, 5,1);
            DateTime arrival = new DateTime(2016, 6, 1);
            DateTime arrival2 = new DateTime(2016, 7, 1);
            DateTime departure1 = new DateTime(2016, 4, 1);
            DateTime arriva1l = new DateTime(2016, 3,1);
            DateTime arrival22 = new DateTime(2016, 2, 1);
            dt.Rows.Add(30,32, departure);
            dt.Rows.Add(42,36, arrival);
            dt.Rows.Add(54,38, arrival2);
            dt.Rows.Add(74,31, departure1);
            dt.Rows.Add(24,30, arriva1l);
            dt.Rows.Add(64,28, arrival22);
            //Chart1.DataBindTable(dt.AsDataView(), "dateNow");
            Chart1.Series["Series1"].ChartType = SeriesChartType.Column;
            //Chart1.Series["Series2"].ChartType = SeriesChartType.Column;
            //Chart1.Series["Series1"]["DrawingStyle"] = "Emboss";
 
            Chart1.DataSource = dt;
            Chart1.Series["Series1"].YValueMembers = "weightNow";
            Chart1.Series["Series1"].XValueMember = "dateNow";
            Chart1.Series["Series1"].XValueType = ChartValueType.DateTime;
            Chart1.Series["Series2"].YValueMembers = "weightNow2";
            Chart1.Series["Series2"].XValueMember = "dateNow";
            Chart1.Series["Series2"].XValueType = ChartValueType.DateTime;
            //Chart1.ChartAreas["ChartArea1"].AxisX.LabelStyle.Format = "yyyy-MM-dd";
            Chart1.Series["Series2"].ChartArea = "ChartArea2";
            Chart1.DataBind();
}

Best Regards,

Brando

Answer 2

User537440814 posted

Hello Brando ZWZ, 

Inspired by your demo, I set XValueType for each series, then everything is fine. Thanks！

Chart1.Series["Series1"].XValueType = ChartValueType.DateTime;