C＃图表中X轴上的时间

Question

I have the following graphic in my Windows Form :

I set the X axis to display Time, as shown below:

Here are the methods I call to draw the graph:

        private void funcaoQualquer()
        {
            while (true)
            {
                funcaoArray[funcaoArray.Length - 1] = hScrollBar1.Value;
                Array.Copy(funcaoArray, 1, funcaoArray, 0, funcaoArray.Length - 1);
                if (chart1.IsHandleCreated)
                {
                    this.Invoke((MethodInvoker)delegate { atualizaGraficoFuncaoQualquer(hScrollBar1.Value); });
                }
                else
                {
                    //...
                }
                Thread.Sleep(250);
            }
        }

        private void atualizaGraficoFuncaoQualquer(int valor)
        {
            for (int i = 0; i < funcaoArray.Length - 1; ++i)
            {
                chart1.Series["Series1"].Points.Add(valor);
            }
        }

However, when drawing the graph and over time, the X axis does not change the values. I think it's being displayed as hours. How do I change to minutes or seconds?

Answer 1

you could set the Format like this:

this.chart1.ChartAreas[0].AxisX.LabelStyle.Format = "mm:ss";

if you have a sampling rate of 4 Hz you could also use seconds and milliseconds:

this.chart1.ChartAreas[0].AxisX.LabelStyle.Format = "ss.fff";

EDIT:

I would suggest to catch the sampling times in an extra List<DateTime> and feed the chart via AddXY with values. Here is a simple programm that draws a curve with a timer. The timer is set to 500 msec.

// Constructor
public Form1()
{
    InitializeComponent();
    // Format
    this.chart1.ChartAreas[0].AxisX.LabelStyle.Format = "ss.fff";
    // this sets the type of the X-Axis values
    chart1.Series[0].XValueType = ChartValueType.DateTime;
    timer1.Start();
}

int i = 0;
List<DateTime> TimeList = new List<DateTime>();

private void timer1_Tick(object sender, EventArgs e)
{
    DateTime now = DateTime.Now;
    TimeList.Add(now);

    chart1.Series[0].Points.AddXY(now, Math.Sin(i / 60.0));
    i+=2;
}

Now you can watch the x-axis values increment in the format that you like. Hope this helps