c# - C# WPF 应用程序中的动态折线图

Question

我在 WPF 下用 C#.Net 开发一个 GUI。实际上它是一个与嵌入式设备进行串行通信的应用程序，我想显示一个包含经常收到的数据的折线图。我还应该提供一个选项来保存这些图表并提供打印它的选项。如何在免费库或软件的支持下动态绘制它？

Answer 1

我使用 Dynamic Data Display满足我所有的 WPF 图表需求。它支持保存图表，速度非常快，提供无缝缩放和平移。命名空间:xmlns:d3="http://research.microsoft.com/DynamicDataDisplay/1.0"

XAML:

 <d3:ChartPlotter Name="plotter" Background="White">
    <d3:ChartPlotter.Resources>
        <conv:Date2AxisConverter x:Key="Date2AxisConverter"/>
    </d3:ChartPlotter.Resources>
    <d3:ChartPlotter.HorizontalAxis>
        <d3:HorizontalDateTimeAxis Name="dateAxis"/>
    </d3:ChartPlotter.HorizontalAxis>
    <d3:Header Content="{Binding PlotHeader}"/>
    <d3:VerticalAxisTitle Content="Value"/>
    <d3:HorizontalAxisTitle Content="Date"/>
</d3:ChartPlotter>

C#代码:使用转换器

public class Date2AxisConverter : IValueConverter
{
    #region IValueConverter Members
    public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        if (value is DateTime && targetType == typeof(double))
        {
            return ((DateTime)value).Ticks / 10000000000.0;
            // See constructor of class Microsoft.Research.DynamicDataDisplay.Charts.DateTimeAxis
            // File: DynamicDataDisplay.Charts.Axes.DateTime.DateTimeAxis.cs

            // alternatively, see the internal class Microsoft.Research.DynamicDataDisplay.Charts.DateTimeToDoubleConversion

        }
        return null;
    }

    public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        // try Microsoft.Research.DynamicDataDisplay.Charts.DateTimeAxis.DoubleToDate
        throw new NotSupportedException();
    }

    #endregion
}

C# 代码:清除图形和创建折线图，这里我的 StockasticProcessPoint 是一个包含字段“DateTime t”和字段“Double value”的结构。

using Microsoft.Research.DynamicDataDisplay;
using System.Collections.ObjectModel;
using Microsoft.Research.DynamicDataDisplay.DataSources;

public void ClearLines()
{
    var lgc = new Collection<IPlotterElement>();
    foreach (var x in plotter.Children)
    {
        if (x is LineGraph || x is ElementMarkerPointsGraph)
            lgc.Add(x);
    }

    foreach (var x in lgc)
    {
        plotter.Children.Remove(x);
    }
}

internal void SendToGraph() {

    IPointDataSource _eds = null;
    LineGraph line;

    ClearLines();

    EnumerableDataSource<StochasticProcessPoint> _edsSPP;
    _edsSPP = new EnumerableDataSource<StochasticProcessPoint>(myListOfStochasticProcessPoints);
    _edsSPP.SetXMapping(p => dateAxis.ConvertToDouble(p.t));
    _edsSPP.SetYMapping(p => p.value);
    _eds = _edsSPP;

    line = new LineGraph(_eds);
    line.LinePen = new Pen(Brushes.Black, 2);
    line.Description = new PenDescription(Description);
    plotter.Children.Add(line);
    plotter.FitToView();
}

有了这个，您应该能够在 WPF 中绘制图表。从串口返回时实时添加数据应该没问题。您还可以查看 DynamicDataDisplay 中的绑定(bind)示例。