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GridContextMenuDefaultItemNames Class

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GridContextMenuDefaultItemNames Class

Contains names of built-in Grid commands.

Namespace : DevExpress.Blazor

Assembly : DevExpress.Blazor.v25.2.dll

NuGet Package : DevExpress.Blazor

Declaration

csharp
public static class GridContextMenuDefaultItemNames

Remarks

The DevExpress Blazor Grid allows you to display context menus with predefined and custom commands. Use the ContextMenus property to activate context menus for specific Grid elements.

Run Demo: Context Menu

Handle the CustomizeContextMenu event to modify the menu item collection. In the event handler, use GridContextMenuDefaultItemNames fields to apply the following customizations:

  • Access and customize built-in context menu items
  • Add built-in items to Grid context menus
  • Remove built-in items from a context menu

Example

The following code snippet customizes commands available in the header context menu:

razor
@inject WeatherForecastService ForecastService

<DxGrid Data="@Data" 
        ContextMenus="GridContextMenus.Header | GridContextMenus.DataRow"
        CustomizeContextMenu="CustomizeContextMenu">
    <Columns>
        <DxGridSelectionColumn />
        <DxGridDataColumn FieldName="Date" DisplayFormat="D" />
        <DxGridDataColumn FieldName="TemperatureC" Caption="@("Temp. (\x2103)")" Width="120px" />
        <DxGridDataColumn FieldName="TemperatureF" Caption="@("Temp. (\x2109)")" Width="120px" />
        <DxGridDataColumn FieldName="Forecast" />
        <DxGridDataColumn FieldName="CloudCover" />
    </Columns>
</DxGrid>

@code {
    object Data { get; set; }

    protected override void OnInitialized() {
        Data = ForecastService.GetForecast();
    }
    void CustomizeContextMenu(GridCustomizeContextMenuEventArgs args) {
        if (args.Context is GridHeaderCommandContext headerContext) {
            // Changes the "ClearColumnSorting" command caption
            args.Items[GridContextMenuDefaultItemNames.ClearColumnSorting].Text = "Unsort";
            // Removes "GroupByColumn"/"UngroupColumn" commands for the Date column header
            if (headerContext.Column is IGridDataColumn dataColumn && dataColumn.FieldName == "Date") {
                args.Items.Remove(GridContextMenuDefaultItemNames.GroupByColumn);
                args.Items.Remove(GridContextMenuDefaultItemNames.UngroupColumn);
            }         
        }
        // Adds built-in items to data row context menus
        if (args.Context is GridDataRowCommandContext rowContext) {
            args.Items.Add(GridContextMenuDefaultItemNames.ExpandAll);
            args.Items.Add(GridContextMenuDefaultItemNames.CollapseAll);
        }
    }
}
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>();

Inheritance

Object GridContextMenuDefaultItemNames

See Also

GridContextMenuDefaultItemNames Members

DevExpress.Blazor Namespace