ChartSeriesLabelModel Class

Defines a point’s label settings.

Namespace: DevExpress.Blazor

Assembly: DevExpress.Blazor.v20.2.dll

NuGet Package: DevExpress.Blazor

Declaration

public class ChartSeriesLabelModel :
    DxModel<ChartSeriesLabelModel>

Related API Members

The following members return ChartSeriesLabelModel objects:

• ChartSeriesPointCustomizationSettings.PointLabel

Remarks

The PointLabel property returns instances of the ChartSeriesLabelModel class. Use this property in the CustomizeSeriesPoint event handler to specify the label color, position, connector, and visibility.

The class instance’s available properties are listed below:

• BackgroundColor
• Connector
• Position
• Visible

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);
}

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());
    }
}

Startup

public class Startup {
//...
    public void ConfigureServices(IServiceCollection services) {
    //...
        services.AddSingleton<WeatherForecastService>();
        //...
    }
    //...
}

Run Demo: Charts - Series Label Customization

Implements

IDisposable

INotifyPropertyChanged

Inheritance

Object

DxModel

DxModel<ChartSeriesLabelModel>

ChartSeriesLabelModel