基于WPF的开源图表控件有很多，大多数都是静态图表，如果需要绘制CPU使用率这样的动态数据就显得力不从心，微软开源的DynamicDataDisplay控件弥补了这个不足，为了做个备忘，我用它来实时绘制CPU使用率曲线，当然，这个控件也可以绘制动态线图、气泡图和热力图，具体可参阅官网示例代码，使用方法非常简单，下面就直接贴代码，文本末尾提供VS2013的示例代码下载。

1、首先需要在项目中引用DynamicDataDisplay.dll，该程序集可通过官网下载或者NuGet方式搜索获去，在包控制台执行以下命令即可自动引用。

PM> Install-Package DynamicDataDisplay

2、在XAML文件中引用D3命名空间，同时添加一个名为ChartPlotter的图表控件。

<Window x:Class="WpfCpuUsageSample.MainWindow" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:d3="http://research.microsoft.com/DynamicDataDisplay/1.0" Title="MainWindow" Loaded="Window_Loaded" Height="350" Width="525"> <Grid> <d3:ChartPlotter Grid.Column="0" Grid.Row="0" Name="plotter"/> </Grid> </Window>

3、在后台窗体类中申明数据源ObservableDataSource用于为图表控件提供数据，PerformanceCounter是性能计数器，可通过它来获取CPU使用率，DispatcherTimer是一个基于WPF的计时器，支持在子线程异步通知UI线程，在窗口加载事件中初始化这些类，并未计时器绑定一个处理程序，用于获取CPU使用率，并将当前的使用率加入到动态曲线中。

public partial class MainWindow : Window { private ObservableDataSource<Point> dataSource = new ObservableDataSource<Point>(); private PerformanceCounter performanceCounter = new PerformanceCounter(); private DispatcherTimer dispatcherTimer = new DispatcherTimer(); private int currentSecond = 0;

</span><span style="color: blue;">public </span><span style="color: black;">MainWindow()
{
    InitializeComponent();
}

</span><span style="color: blue;">private void </span><span style="color: black;">Window_Loaded(</span><span style="color: blue;">object </span><span style="color: black;">sender, </span><span style="color: #2b91af;">RoutedEventArgs </span><span style="color: black;">e)
{
    plotter.AddLineGraph(dataSource, </span><span style="color: #2b91af;">Colors</span><span style="color: black;">.Green, 2, </span><span style="color: #a31515;">"Percentage"</span><span style="color: black;">);
    plotter.LegendVisible = </span><span style="color: blue;">false</span><span style="color: black;">;
    dispatcherTimer.Interval = </span><span style="color: #2b91af;">TimeSpan</span><span style="color: black;">.FromSeconds(1);
    dispatcherTimer.Tick += timer_Tick;
    dispatcherTimer.IsEnabled = </span><span style="color: blue;">true</span><span style="color: black;">;
    plotter.Viewport.FitToView();
}

</span><span style="color: blue;">private void </span><span style="color: black;">timer_Tick(</span><span style="color: blue;">object </span><span style="color: black;">sender, </span><span style="color: #2b91af;">EventArgs </span><span style="color: black;">e)
{
    performanceCounter.CategoryName = </span><span style="color: #a31515;">"Processor"</span><span style="color: black;">;
    performanceCounter.CounterName = </span><span style="color: #a31515;">"% Processor Time"</span><span style="color: black;">;
    performanceCounter.InstanceName = </span><span style="color: #a31515;">"_Total"</span><span style="color: black;">;

    </span><span style="color: blue;">double </span><span style="color: black;">x = currentSecond;
    </span><span style="color: blue;">double </span><span style="color: black;">y = performanceCounter.NextValue();

    </span><span style="color: #2b91af;">Point </span><span style="color: black;">point = </span><span style="color: blue;">new </span><span style="color: #2b91af;">Point</span><span style="color: black;">(x, y);
    dataSource.AppendAsync(</span><span style="color: blue;">base</span><span style="color: black;">.Dispatcher, point);

    currentSecond++;
}

}