SplineArea Chart

SplineArea charts are specialized forms of conventional line and area charts. It is useful when you want to show smooth gradual changes instead of spikes.

The chart from the image above is created with the following code:

<shield:ShieldChart ID="ShieldChart1" Width="580px" Height="400px" runat="server" 
    OnTakeDataSource="ShieldChart1_TakeDataSource"
    CssClass="chart">
    <PrimaryHeader Text="Twitter Usage Trends October 2010"></PrimaryHeader>
    <Axes>
        <shield:ChartAxisX  AxisType="Datetime" FixedEnd="false"></shield:ChartAxisX>
        <shield:ChartAxisY EndOffset="0">
        </shield:ChartAxisY>
    </Axes>
    <DataSeries>
        <shield:ChartSplineAreaSeries>
        </shield:ChartSplineAreaSeries>
    </DataSeries>
</shield:ShieldChart>

protected override void OnLoad(EventArgs e)
{
    base.OnLoad(e);
    (ShieldChart1.DataSeries[0] as Shield.Web.UI.ChartSplineAreaSeries).DataStart = (decimal)(new DateTime(2010, 1, 1) -
        new DateTime(1970, 1, 1).ToUniversalTime()).TotalMilliseconds;
    (ShieldChart1.DataSeries[0] as Shield.Web.UI.ChartSplineAreaSeries).DataStep = 24 * 3600 * 1000;
}

protected void ShieldChart1_TakeDataSource(object sender, Shield.Web.UI.ChartTakeDataSourceEventArgs e)
{
    List datasource = new List() { 
        29.9, 71.5, 106.4, 129.2, 144.0, 176.0, 135.6, 148.5, 216.4, 194.1, 95.6, 54.4 };

    ShieldChart1.DataSource = datasource;
}

• When the chart is bound to collection of objects the X values are got by the field which name is set into the DataFieldX property of the ChartSplineAreaSeries. The Y values are got by the field which name is set into the DataFieldY property.
• The name that is shown in the legend is chosen via the CollectionAlias property of the ChartSplineAreaSeries.
• By default all X values are sorted in order splinearea chart to be shown appropriately, however this behavior is controlled by the EnableValueXSorting property of the ChartSplineAreaSeries.
• The line type of the ChartSplineAreaSeries can be changed by the Settings.SeriesDashStyle property and it can be set as: Solid, ShortDash, ShortDot, ShortDashDot, Dot, etc.
• DataStart and DataStep properties control the start value of the x axis and explicit value for the interval between a data series member values.
• All points from the ChartSplineAreaSeries are represented with ChartSeriesItem which belongs to the ChartSplineAreaSeries.Items collection.
  • The ChartSplineAreaSeries.Items can be added declarative without data binding.
  • The data binding and declarative approach can be mixed. However in order declarative items to be appended to the items created from the datasource the ShieldChart.AppendDataBoundItems property need to be set to "true".
• All setting related to ChartSplineAreaSeries are contained into the ChartSplineAreaSeries.Settings object.
  • The background and line color can be set via Color and InnerColor properties..
  • If the AddToLegend is set to false the series is not added into the legend.
  • The animation of the series can be controlled by ChartSplineAreaSeries.Settings.EnableAnimation and ChartSplineAreaSeries.Settings.AnimationDuration properties.
  • If some values are missing (i.e. they are null/Nothing) from the series data you can have the chart work around this by setting the DrawNullValues property.
  • The series of multiline area chart can be stacked by setting the StackMode property to Normal or Percent.
  • Each point from the series can be selected if the EnablePointSelection property is set to true.
  • All selected points can be customized by Settings.PointMark.ActiveSettings.PointSelectedState object properties.
  • Each series has related tooltip which can be customized via the Settings.Tooltip object.
  • Each point from the series can have related text, which appearance is controlled by Settings.DataPointText property. You can changeBackgroundColor, BorderColor, Color, Padding, and TextAngle of the corresponding data point text.