如何使用c＃设置日期时间图表的最小值和最大值？

Question

我试图在我的Windows应用程序中每隔一秒绘制一个带有实时数据的折线图。为此，我需要为图表设置最小值（0秒）和最大值（10分钟）。 10分钟后，最小值为10分钟，最大值为20分钟。所以我每次都要显示10分钟的数据。我需要从一开始就用滚动条显示以前的数据。我尝试了以下代码，但我无法设置图表的最小值和最大值。请解决我的问题。

   series1.XValueType = ChartValueType.DateTime;
   series1.IsXValueIndexed = true;
   series1.YAxisType = AxisType.Primary;
   series1.ChartType = SeriesChartType.Line;           
   this.chart1.Series.Add(series1);    

   series2.XValueType = ChartValueType.DateTime;
   series2.IsXValueIndexed = true;
   series2.YAxisType = AxisType.Secondary;
   series2.ChartType = SeriesChartType.Line;
   this.chart1.Series.Add(series2);

   chart1.ChartAreas[0].AxisX.LabelStyle.Format = "HH:mm:ss";
    chart1.ChartAreas[0].CursorX.IntervalType = DateTimeIntervalType.Seconds;

   chart1.ChartAreas[0].CursorX.AutoScroll = true;
   chart1.ChartAreas[0].CursorY.AutoScroll = true;

   chart1.ChartAreas[0].AxisX.ScrollBar.Size = 15;
   chart1.ChartAreas[0].AxisX.ScrollBar.ButtonStyle = ScrollBarButtonStyles.All;
   chart1.ChartAreas[0].AxisX.ScrollBar.IsPositionedInside = false;
   chart1.ChartAreas[0].AxisX.ScrollBar.Enabled = true;

   chart1.ChartAreas[0].AxisX.ScaleView.Zoomable = true;
   chart1.ChartAreas[0].AxisY.ScaleView.Zoomable = true;
   chart1.ChartAreas[0].AxisY2.ScaleView.Zoomable = true;

   chart1.ChartAreas[0].CursorX.IsUserEnabled = true;
   chart1.ChartAreas[0].CursorX.IsUserSelectionEnabled = true;

   DateTime minValue, maxValue;
   minValue = DateTime.Now;
   maxValue = minValue.AddSeconds(600);

   chart1.ChartAreas[0].AxisX.Minimum = minValue.ToOADate();
   chart1.ChartAreas[0].AxisX.Maximum = maxValue.ToOADate();
   chart1.ChartAreas[0].AxisX.ScaleView.Zoom(chart1.ChartAreas[0].AxisX.Minimum, chart1.ChartAreas[0].AxisX.Maximum);  

Answer 1

Microsoft有一个他们为找到的mscharts here做的示例项目。在Working with Data目录中，有一个实时数据部分。他们有一个互动的例子做你要求的。为方便起见，我复制了以下代码。希望这会有所帮助。

using System.Windows.Forms.DataVisualization.Charting;
...
private Thread addDataRunner;
private Random rand = new Random();
private System.Windows.Forms.DataVisualization.Charting.Chart chart1;
public delegate void AddDataDelegate();
public AddDataDelegate addDataDel;
...

private void RealTimeSample_Load(object sender, System.EventArgs e)
{

    // create the Adding Data Thread but do not start until start button clicked
    ThreadStart addDataThreadStart = new ThreadStart(AddDataThreadLoop);
    addDataRunner = new Thread(addDataThreadStart);

    // create a delegate for adding data
    addDataDel += new AddDataDelegate(AddData);

}

private void startTrending_Click(object sender, System.EventArgs e)
{
    // Disable all controls on the form
    startTrending.Enabled = false;
    // and only Enable the Stop button
    stopTrending.Enabled = true;

    // Predefine the viewing area of the chart
    minValue = DateTime.Now;
    maxValue = minValue.AddSeconds(120);

    chart1.ChartAreas[0].AxisX.Minimum = minValue.ToOADate();
    chart1.ChartAreas[0].AxisX.Maximum = maxValue.ToOADate();

    // Reset number of series in the chart.
    chart1.Series.Clear();

    // create a line chart series
    Series newSeries = new Series( "Series1" );
    newSeries.ChartType = SeriesChartType.Line;
    newSeries.BorderWidth = 2;
    newSeries.Color = Color.OrangeRed;
    newSeries.XValueType = ChartValueType.DateTime;
    chart1.Series.Add( newSeries );    

    // start worker threads.
    if ( addDataRunner.IsAlive == true )
    {
        addDataRunner.Resume();
    }
    else
    {
        addDataRunner.Start();
    }

}

private void stopTrending_Click(object sender, System.EventArgs e)
{
    if ( addDataRunner.IsAlive == true )
    {
        addDataRunner.Suspend();
    }

    // Enable all controls on the form
    startTrending.Enabled = true;
    // and only Disable the Stop button
    stopTrending.Enabled = false;
}

/// Main loop for the thread that adds data to the chart.
/// The main purpose of this function is to Invoke AddData
/// function every 1000ms (1 second).
private void AddDataThreadLoop()
{
    while (true)
    {
        chart1.Invoke(addDataDel);

        Thread.Sleep(1000);
    }
}

public void AddData()
{
    DateTime timeStamp = DateTime.Now;

    foreach ( Series ptSeries in chart1.Series )
    {
        AddNewPoint( timeStamp, ptSeries );
    }
}

/// The AddNewPoint function is called for each series in the chart when
/// new points need to be added.  The new point will be placed at specified
/// X axis (Date/Time) position with a Y value in a range +/- 1 from the previous
/// data point's Y value, and not smaller than zero.
public void AddNewPoint( DateTime timeStamp, System.Windows.Forms.DataVisualization.Charting.Series ptSeries )
{
    double newVal = 0;

    if ( ptSeries.Points.Count > 0 )
    {
        newVal = ptSeries.Points[ptSeries.Points.Count -1 ].YValues[0] + (( rand.NextDouble() * 2 ) - 1 );
    }

    if ( newVal < 0 )
        newVal = 0;

    // Add new data point to its series.
    ptSeries.Points.AddXY( timeStamp.ToOADate(), rand.Next(10, 20));

    // remove all points from the source series older than 1.5 minutes.
    double removeBefore = timeStamp.AddSeconds( (double)(90) * ( -1 )).ToOADate();
    //remove oldest values to maintain a constant number of data points
    while ( ptSeries.Points[0].XValue < removeBefore )
    {
        ptSeries.Points.RemoveAt(0);
    }

    chart1.ChartAreas[0].AxisX.Minimum = ptSeries.Points[0].XValue;
    chart1.ChartAreas[0].AxisX.Maximum = DateTime.FromOADate(ptSeries.Points[0].XValue).AddMinutes(2).ToOADate();

    chart1.Invalidate();
}

/// Clean up any resources being used.
protected override void Dispose( bool disposing )
{
    if ( (addDataRunner.ThreadState & ThreadState.Suspended) == ThreadState.Suspended)
    {
        addDataRunner.Resume();
    }
    addDataRunner.Abort();

    if( disposing )
    {
        if (components != null) 
        {
            components.Dispose();
        }
    }
    base.Dispose( disposing );
}        
... 

Answer 2

  

最后，我找到了解决问题的方法，对代码进行了一些修改。感谢您的支持。我实现了一个包含两个系列的折线图，图表必须在每一帧中显示1分钟的数据。

    int viewcount=0,count=0,mviewcount=60;
    public void AddData() // executing using thread
    {
        while (true)
        {
            if (flag) // making flag as true by calling timer for every 1sec
            {
                flag = false;
                DateTime timeStamp = DateTime.Now;

                double y1 = 0.0;
                double y2= 0.0;

                y1= gety1(count);
                y2= gety2(count + 1);

                AddNewPoint(timeStamp, chart1.Series[0], chart1.Series[1], oilvalue, tempvalue);


                count++;
            }
            Thread.Sleep(1);
        }
    }

   public void AddNewPoint(DateTime timeStamp, System.Windows.Forms.DataVisualization.Charting.Series ptSeries1, System.Windows.Forms.DataVisualization.Charting.Series ptSeries2, double y1, double y2)
    {
        if (this.chart1.InvokeRequired)
        {
            BeginInvoke((Action)(() =>
            {                  
                this.chart1.Series[0].Points.AddXY(timeStamp.ToOADate(), y1);
                this.chart1.Series[1].Points.AddXY(timeStamp.ToOADate(), y2);

                if ((count % 60) == 0)
                {                
                    mviewcount += 60;
                    viewcount += 60;

                    chart1.ChartAreas[0].AxisX.Minimum = DateTime.FromOADate(ptSeries1.Points[count - 1].XValue).ToOADate(); 
                    chart1.ChartAreas[0].AxisX.Maximum = DateTime.FromOADate(ptSeries1.Points[count - 1].XValue).AddMinutes(1).ToOADate();                        
                    min = chart1.ChartAreas[0].AxisX.Minimum;
                    max = chart1.ChartAreas[0].AxisX.Maximum;                       
                }

                if (count >= 60)
                {
                    if ((count >= viewcount) || (count <= mviewcount))
                    {                        
                        chart1.Series[0].Points[0].AxisLabel = System.DateTime.FromOADate(chart1.Series[0].Points[count - 1].XValue).ToString();
                        chart1.ChartAreas[0].AxisX.ScaleView.Position = max;
                    }
                }                    

                chart1.Update();
                chart1.ChartAreas[0].RecalculateAxesScale();

            }));
        }
    }

Answer 3

我在工作。实时60分钟。

        if (this.chart1.InvokeRequired)
        {
            BeginInvoke((Action)(() =>
            {
                if (!chartState) return;

                DateTime now = DateTime.Now;
                chart1.ResetAutoValues();

                for (int i = 0; i < chart1.Series.Count; i++)
                {
                    if (chart1.Series[i].Points.Count > 0)
                    {
                        while (chart1.Series[i].Points[0].XValue < now.AddMinutes(-60).ToOADate())
                        {
                            chart1.Series[i].Points.RemoveAt(0);

                            chart1.ChartAreas[0].AxisX.Minimum = chart1.Series[i].Points[0].XValue;
                            chart1.ChartAreas[0].AxisX.Maximum = now.AddMinutes(1).ToOADate();
                        }
                    }
                }

                chart1.Series["Sebeke"].Points.AddXY(now.ToOADate(), AnlikSebeke);
                chart1.Series["Turbin"].Points.AddXY(now.ToOADate(), AnlikTurbin);
                chart1.Series["Tuketim"].Points.AddXY(now.ToOADate(), AnlikTuketim);
                chart1.Invalidate();
            }));
        }