ChartDataLabel

ChartDataLabel class

Represents data label on a chart point or trendline.

To learn more, visit the Working with Charts documentation article.

public class ChartDataLabel

Properties

Name	Description
Font { get; }	Provides access to the font formatting of this data label.
Format { get; }	Provides access to fill and line formatting of the data label.
Index { get; }	Specifies the index of the containing element. This index shall determine which of the parent’s children collection this element applies to. Default value is 0.
IsHidden { get; set; }	Gets/sets a flag indicating whether this label is hidden. The default value is `false`.
IsVisible { get; }	Returns `true` if this data label has something to display.
NumberFormat { get; }	Returns number format of the parent element.
Orientation { get; set; }	Gets or sets the orientation of the label text.
Rotation { get; set; }	Gets or sets the rotation of the label in degrees.
Separator { get; set; }	Gets or sets string separator used for the data labels on a chart. The default is a comma, except for pie charts showing only category name and percentage, when a line break shall be used instead.
ShowBubbleSize { get; set; }	Allows to specify if bubble size is to be displayed for the data labels on a chart. Applies only to Bubble charts. Default value is `false`.
ShowCategoryName { get; set; }	Allows to specify if category name is to be displayed for the data labels on a chart. Default value is `false`.
ShowDataLabelsRange { get; set; }	Allows to specify if values from data labels range to be displayed in the data labels. Default value is `false`.
ShowLeaderLines { get; set; }	Allows to specify if data label leader lines need be shown. Default value is `false`.
ShowLegendKey { get; set; }	Allows to specify if legend key is to be displayed for the data labels on a chart. Default value is `false`.
ShowPercentage { get; set; }	Allows to specify if percentage value is to be displayed for the data labels on a chart. Default value is `false`.
ShowSeriesName { get; set; }	Returns or sets a Boolean to indicate the series name display behavior for the data labels on a chart. `true` to show the series name; `false` to hide. By default `false`.
ShowValue { get; set; }	Allows to specify if values are to be displayed in the data labels. Default value is `false`.

Methods

Name	Description
ClearFormat()	Clears format of this data label. The properties are set to the default values defined in the parent data label collection.

Remarks

On a series, the ChartDataLabel object is a member of the ChartDataLabelCollection. The ChartDataLabelCollection contains a ChartDataLabel object for each point.

Examples

Shows how to apply labels to data points in a line chart.

public void DataLabels()
{
    Document doc = new Document();
    DocumentBuilder builder = new DocumentBuilder(doc);

    Shape chartShape = builder.InsertChart(ChartType.Line, 400, 300);
    Chart chart = chartShape.Chart;

    Assert.AreEqual(3, chart.Series.Count);
    Assert.AreEqual("Series 1", chart.Series[0].Name);
    Assert.AreEqual("Series 2", chart.Series[1].Name);
    Assert.AreEqual("Series 3", chart.Series[2].Name);

    // Apply data labels to every series in the chart.
    // These labels will appear next to each data point in the graph and display its value.
    foreach (ChartSeries series in chart.Series)
    {
        ApplyDataLabels(series, 4, "000.0", ", ");
        Assert.AreEqual(4, series.DataLabels.Count);
    }

    // Change the separator string for every data label in a series.
    using (IEnumerator<ChartDataLabel> enumerator = chart.Series[0].DataLabels.GetEnumerator())
    {
        while (enumerator.MoveNext())
        {
            Assert.AreEqual(", ", enumerator.Current.Separator);
            enumerator.Current.Separator = " & ";
        }
    }

    // For a cleaner looking graph, we can remove data labels individually.
    chart.Series[1].DataLabels[2].ClearFormat();

    // We can also strip an entire series of its data labels at once.
    chart.Series[2].DataLabels.ClearFormat();

    doc.Save(ArtifactsDir + "Charts.DataLabels.docx");
}

/// <summary>
/// Apply data labels with custom number format and separator to several data points in a series.
/// </summary>
private static void ApplyDataLabels(ChartSeries series, int labelsCount, string numberFormat, string separator)
{
    for (int i = 0; i < labelsCount; i++)
    {
        series.HasDataLabels = true;

        Assert.False(series.DataLabels[i].IsVisible);

        series.DataLabels[i].ShowCategoryName = true;
        series.DataLabels[i].ShowSeriesName = true;
        series.DataLabels[i].ShowValue = true;
        series.DataLabels[i].ShowLeaderLines = true;
        series.DataLabels[i].ShowLegendKey = true;
        series.DataLabels[i].ShowPercentage = false;
        series.DataLabels[i].IsHidden = false;
        Assert.False(series.DataLabels[i].ShowDataLabelsRange);

        series.DataLabels[i].NumberFormat.FormatCode = numberFormat;
        series.DataLabels[i].Separator = separator;

        Assert.False(series.DataLabels[i].ShowDataLabelsRange);
        Assert.True(series.DataLabels[i].IsVisible);
        Assert.False(series.DataLabels[i].IsHidden);
    }
}