ChartSeriesPointCustomizationSettings.PointLabel Property

Provides access to the point’s label settings.

Namespace: DevExpress.Blazor

Assembly: DevExpress.Blazor.v23.2.dll

NuGet Package: DevExpress.Blazor

Declaration

public ChartSeriesLabelModel PointLabel { get; }

Property Value

Type	Description
ChartSeriesLabelModel	The point label.

Remarks

Use this property in the CustomizeSeriesPoint event handler to specify the label color, position, and visibility.

To define appearance settings that apply to all the labels in a series, use the DxChartSeriesLabel component.

Tip

Individual label settings have a priority over the common label settings.

The following example demonstrates how to:

• use the DxChartSeriesLabel component to specify the position of all labels;
• use the DxChartSeriesLabelConnector component to customize connectors between data points and labels;
• handle the CustomizeSeriesPoint event to show only labels whose values are between 25 and 75.

Razor

@inject WeatherForecastService ForecastService

<DxChart Data="@ChartData" CustomizeSeriesPoint="@PreparePointLabel">
    <DxChartLineSeries AggregationMethod="@(i => (int)i.Average())"
                       ValueField="@((WeatherForecast i) => i.TemperatureF)"
                       ArgumentField="@(i => i.Date.Date)"
                       Name="Temperature, F">
        <DxChartSeriesLabel Position="RelativePosition.Outside">
            <DxChartSeriesLabelConnector Visible="true" Width="3" />
        </DxChartSeriesLabel>
    </DxChartLineSeries>
</DxChart>

@code {
    WeatherForecast[] ChartData;

    protected override async Task OnInitializedAsync() {
        ChartData = await ForecastService.GetForecastAsync();
    }

    protected void PreparePointLabel(ChartSeriesPointCustomizationSettings pointSettings) {
        double value = (double)pointSettings.Point.Value;
        if (value > 25 && value < 75)
            pointSettings.PointLabel.Visible = true;
    }
}

WeatherForecast

using System;

public class WeatherForecast {
    public DateTime Date { get; set; }
    public int TemperatureC { get; set; }
    public double TemperatureF => Math.Round((TemperatureC * 1.8 + 32), 2);
    public double Precipitation { get; set; }
}

WeatherForecastService

    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Threading;
    using System.Threading.Tasks;

    public class WeatherForecastService {
    // ...
        private List<WeatherForecast> Forecast { get; set; }

        public WeatherForecastService() {
        // ...
            Forecast = CreateForecast();
        }

// ...
        private List<WeatherForecast> CreateForecast() {
            var rng = new Random();
            DateTime startDate = DateTime.Now;
            return Enumerable.Range(1, 15).Select(index => new WeatherForecast {
                Date = startDate.AddDays(index),
                TemperatureC = rng.Next(-20, 55),
            }).ToList();
        }

        public Task<WeatherForecast[]> GetForecastAsync(CancellationToken ct = default) {
            return Task.FromResult(Forecast.ToArray());
        }
    }

Program.cs

// ...
builder.Services.AddSingleton<WeatherForecastService>();

Run Demo: Charts - Series Label Customization