线和点标记

对于一个面积图或折线图，您可能希望有一个标记，标记X-或Y-轴以及数据点。对于可视化参考，一个线或者点标记将类似于以下的图像所示：

要创建这样的一个标记，需要设置的最重要的属性之一是VerticalAlignment 属性。当您设置该属性的值为“Stretch”时，标记将拉伸至整个绘图区高度，以提供垂直线。下面是您将在标记中设置的属性：

Attach = DataX
Action = MouseMove
DataPoint = -1, NaN
HorizontalAlignment = Center
VerticalContentAlignment = Stretch

请注意，您正在设置数据点的Y部分的值为NaN。这也将有助于设置完全的的垂直线，因为标记永远不会附加到一个特定的数据点。上图中的圆形标签是另一个ChartPanelObject 对象，该对象将放置在绘图区元素上。它的DataPoint属性将被设置为非NaN的值。

您可以只使用XAML标记创建这种效果，完全不需要添加任何代码！

XAML	拷贝代码
<!-- 垂直线以及点标记 --> <c1:ChartPanelObject x:Name="vline" Attach="DataX" Action="MouseMove" DataPoint="-1, NaN" VerticalContentAlignment="Stretch" HorizontalAlignment="Center"> <Border Background="Black" BorderBrush="Black" Padding="1" BorderThickness="1 0 0 0" /> </c1:ChartPanelObject> <c1:ChartPanelObject x:Name="dot" Attach="DataX" Action="MouseMove" DataPoint="0.5,0.5" HorizontalAlignment="Center" VerticalAlignment="Center"> <Grid DataContext="{Binding RelativeSource={x:Static RelativeSource.Self},Path=Parent}"> <Ellipse Fill="White" Stroke="Black" StrokeThickness="1" Width="30" Height="30" /> <TextBlock x:Name="label" Text="{Binding DataPoint.Y, StringFormat=n0}" FontWeight="Bold" VerticalAlignment="Center" HorizontalAlignment="Center"/> </Grid> </c1:ChartPanelObject>

XAML

拷贝代码

<!-- 垂直线以及点标记 -->
<c1:ChartPanelObject x:Name="vline"
                     Attach="DataX"
                     Action="MouseMove"
                     DataPoint="-1, NaN"
                     VerticalContentAlignment="Stretch"
                     HorizontalAlignment="Center">
        <Border Background="Black" BorderBrush="Black" Padding="1" BorderThickness="1 0 0 0" />
</c1:ChartPanelObject>
<c1:ChartPanelObject x:Name="dot"
                     Attach="DataX"
                     Action="MouseMove"
                     DataPoint="0.5,0.5"
                     HorizontalAlignment="Center"
                     VerticalAlignment="Center">
    <Grid DataContext="{Binding RelativeSource={x:Static RelativeSource.Self},Path=Parent}">
        <Ellipse Fill="White" Stroke="Black" StrokeThickness="1" Width="30" Height="30" />
        <TextBlock x:Name="label" Text="{Binding DataPoint.Y, StringFormat=n0}" FontWeight="Bold" VerticalAlignment="Center" HorizontalAlignment="Center"/>
    </Grid>
</c1:ChartPanelObject>

查看其它

十字线标记