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IGridColumn Interface

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IGridColumn Interface

An interface that defines a Grid column’s API members (properties and methods).

Namespace : DevExpress.Blazor

Assembly : DevExpress.Blazor.v25.2.dll

NuGet Package : DevExpress.Blazor

Declaration

csharp
public interface IGridColumn

The following members return IGridColumn objects:

Remarks

We recommend that you use the IGridColumn interface when you access a Grid column’s API members in any of the following cases:

  • You use the @ref attribute to reference a Grid column. For example, you set or change values of the Grid column’s parameters outside the markup.
  • You access a Column object from templates or event handlers.
  • You access elements of the Grid column collection. For example, the collection that is returned by the GetColumns() method.

In all other cases, bind your data to column parameters.

The following code snippet uses the RowClick event to handle clicks on grid rows. The event’s Column argument (which returns an IGridColumn object) provides access to a grid column against which data rows are grouped.

razor
@inject WeatherForecastService ForecastService

<DxGrid Data="@Data"
        RowClick="OnRowClick"
        AllowGroup="true"
        ShowGroupPanel="true">
    <Columns>
        <DxGridDataColumn FieldName="Date" Caption="Date" />
        <DxGridDataColumn FieldName="TemperatureC" Caption="@("Temp. (\x2103)")" Width="120px" GroupIndex="0"/>
        <DxGridDataColumn FieldName="TemperatureF" Caption="@("Temp. (\x2109)")" Width="120px" />
        <DxGridDataColumn FieldName="Forecast" Caption="Forecast" />
        <DxGridDataColumn FieldName="CloudCover" Caption="CloudCover" GroupIndex="1"/>
    </Columns>
</DxGrid>

@Alert

@code {
    public string Alert { get; set; } = "";
    object Data { get; set; }

    protected override void OnInitialized() {
        Data = ForecastService.GetForecast();
    }

    void OnRowClick(GridRowClickEventArgs e) {
        Alert = $"Data rows are grouped by the {e.Column.Caption} column. ";
    }
}
csharp
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 string Forecast { get; set; }
    public string CloudCover { get; set; }
    public bool Precipitation { get; set; }
}
csharp
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; }

        private static string[] CloudCover = new[] {
            "Sunny", "Partly cloudy", "Cloudy", "Storm"
        };

        Tuple<int, string>[] ConditionsForForecast = new Tuple<int, string>[] {
            Tuple.Create( 22 , "Hot"),
            Tuple.Create( 13 , "Warm"),
            Tuple.Create( 0 , "Cold"),
            Tuple.Create( -10 , "Freezing")
        };

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

        private List<WeatherForecast> CreateForecast() {
            var rng = new Random();
            DateTime startDate = DateTime.Now;
            return Enumerable.Range(1, 15).Select(index => {
                var temperatureC = rng.Next(-10, 30);
                return new WeatherForecast {
                    Date = startDate.AddDays(index),               
                    TemperatureC = temperatureC,
                    CloudCover = CloudCover[rng.Next(0, 4)],
                    Precipitation = Convert.ToBoolean(rng.Next(0, 2)),
                    Forecast = ConditionsForForecast.First(c => c.Item1 <= temperatureC).Item2
                };
            }).ToList();
        }

        public IEnumerable<WeatherForecast> GetForecast() {
            return Forecast.ToArray();
        }
        // ...
}
csharp
// ...
builder.Services.AddSingleton<WeatherForecastService>();

See Also

IGridColumn Members

DevExpress.Blazor Namespace