TreeListExportOptions.ExportSelectedRowsOnly Property

Specifies whether the TreeList exports selected rows only.

Namespace: DevExpress.Blazor

Assembly: DevExpress.Blazor.v25.1.dll

NuGet Package: DevExpress.Blazor

Declaration

[DefaultValue(false)]
public override bool ExportSelectedRowsOnly { get; set; }

Property Value

Type	Default	Description
Boolean	false	true to export the selected rows only; false to export all TreeList rows.

Remarks

Note

If ExportSelectedRowsOnly is enabled, the TreeList component exports data in a flat format (ignores hierarchy). When bound to a hierarchical data source, the component also exports children of each selected row.

The following example exports selected TreeList rows as a flat list:

Razor

@rendermode InteractiveServer
@inject SpaceObjectDataProvider SpaceObjectDataProvider

<DxTreeList @ref="TreeList" Data="TreeListData" ChildrenFieldName="Satellites">
    <Columns>
        <DxTreeListSelectionColumn Width="60px" AllowSelectAll="true" />
        <DxTreeListDataColumn FieldName="Name" />
        <DxTreeListDataColumn FieldName="TypeOfObject" Caption="Type" />
        <DxTreeListDataColumn FieldName="Mass10pow21kg" Caption="Mass, kg" DisplayFormat="N2" />
        <DxTreeListDataColumn FieldName="MeanRadiusInKM" Caption="Radius, km" DisplayFormat="N2"/>
    </Columns>
    <ToolbarTemplate>
        <DxToolbar>
            <DxToolbarItem Text="Export to XLSX" Click="ExportXlsx_Click" BeginGroup="true" />
        </DxToolbar>
    </ToolbarTemplate>
</DxTreeList>

@code {
    ITreeList TreeList { get; set; }
    object TreeListData { get; set; }

    protected override async Task OnInitializedAsync() {
        TreeListData = SpaceObjectDataProvider.GenerateData();
    }
    async Task ExportXlsx_Click() {
        await TreeList.ExportToXlsxAsync("ExportResult", new TreeListXlExportOptions() {
            ExportSelectedRowsOnly = true
        });
    }
}

SpaceObject

using System.Collections.Generic;

public class SpaceObject {
    public string Name { get; set; }
    public double MeanRadiusInKM { get; set; }
    public double Volume10pow9KM3 { get; set; }
    public double Mass10pow21kg { get; set; }
    public double Density { get; set; }
    public double SurfaceGravity { get; set; }
    public string TypeOfObject { get; set; }
    public List<SpaceObject> Satellites { get; set; }
    public SpaceObject(
        string name,
        double meanRadiusInKM,
        double volume10pow9KM3,
        double mass10pow21kg,
        double density,
        double surfaceGravity,
        string typeOfObject,
        List<SpaceObject> satellites = null
    ) {
        Name = name;
        MeanRadiusInKM = meanRadiusInKM;
        Volume10pow9KM3 = volume10pow9KM3;
        Mass10pow21kg = mass10pow21kg;
        Density = density;
        SurfaceGravity = surfaceGravity;
        TypeOfObject = typeOfObject;
        Satellites = satellites ?? new List<SpaceObject>();
    }
}

SpaceObjectDataProvider

public class SpaceObjectDataProvider {
    public List<SpaceObject> GenerateData() {
        return new List<SpaceObject>() {
            new SpaceObject("Sun", 696000, 1412000000, 1989100000, 1.409, 274.0, "Star", new List<SpaceObject>() {
                new SpaceObject("Mercury", 2439.7, 60.83, 330.2, 5.43, 3.7, "Planet"),
                new SpaceObject("Venus", 6051.8, 928.43, 4868.5, 5.24, 8.872, "Planet"),
                new SpaceObject("Earth", 6371.0, 1083.21, 5973.6, 5.515, 9.78033, "Planet", new List<SpaceObject> () {
                    new SpaceObject("Moon", 1737.1, 21.958, 73.5, 3.3464, 1.625, "Satellite")
                }),
                new SpaceObject("Mars", 3390.0, 163.18, 641.85, 3.94, 3.7, "Planet"),
                new SpaceObject("Jupiter", 69911, 1431280, 1898600, 1.33, 24.79, "Planet", new List<SpaceObject>() {
                    new SpaceObject("Ganymede", 2631.2, 76.30, 148.2, 1.936, 1.428, "Satellite"),
                    new SpaceObject("Callisto", 2410.3, 58.65, 107.6, 1.83, 1.23603, "Satellite"),
                    new SpaceObject("Io", 1821.5, 25.32, 89.3, 3.528, 1.797, "Satellite"),
                    new SpaceObject("Europa", 1561, 15.93, 48, 3.01, 1.316, "Satellite"),
                }),
                new SpaceObject("Saturn", 58232, 827130, 568460, 0.70, 10.445, "Planet", new List<SpaceObject>() {
                    new SpaceObject("Titan", 2576, 71.52, 134.5, 1.88, 1.354, "Satellite"),
                    new SpaceObject("Rhea", 764.4, 1.87, 2.3166, 1.23, 0.26, "Satellite"),
                    new SpaceObject("Iapetus", 736, 1.55, 1.9739, 1.08, 0.223, "Satellite"),
                    new SpaceObject("Dione", 561.6, 0.73, 1.096, 1.48, 0.232, "Satellite"),
                    new SpaceObject("Tethys", 533, 0.624, 0.6173, 1.15, 0.145, "Satellite"),
                    new SpaceObject("Enceladus", 252.1, 0.067, 0.108, 1.61, 0.111, "Satellite"),
                    new SpaceObject("Mimas", 198.3, 0.033, 0.03749, 1.15, 0.06363, "Satellite")
                }),
                new SpaceObject("Uranus", 25362, 68340, 86832, 1.30, 8.87, "Planet", new List<SpaceObject>() {
                    new SpaceObject("Titania", 788.9, 2.06, 3.526, 1.72, 0.378, "Satellite"),
                    new SpaceObject("Oberon", 761.4, 1.85, 3.014, 1.63, 0.347, "Satellite"),
                    new SpaceObject("Umbriel", 584.7, 0.84, 1.2, 1.4, 0.234, "Satellite"),
                    new SpaceObject("Ariel", 578.9, 0.81, 1.35, 1.67, 0.269, "Satellite"),
                    new SpaceObject("Miranda", 235.8, 0.055, 0.0659, 1.20, 0.07910375, "Satellite"),
                }),
                new SpaceObject("Neptune", 24622, 62540, 102430, 1.76, 11.15, "Planet", new List<SpaceObject>() {
                    new SpaceObject("Triton", 1353.4, 10.38, 21.5, 2.061, 0.782, "Satellite"),
                    new SpaceObject("Proteus", 210, 0.038, 0.050, 1.3, 0.0666, "Satellite"),
                }),
                new SpaceObject("Eris", 1170, 7, 16.7, 2.25, 0.662, "Dwarf planet"),
                new SpaceObject("Pluto", 1153, 7.15, 13.105, 2.0, 0.61, "Dwarf planet"),
                new SpaceObject("Makemake", 710, 1.8, 3, 2.0, 0.4,  "Dwarf planet"),
                new SpaceObject("Haumea", 575, 1.3, 4.006, 3, 0.44, "Dwarf planet"),
                new SpaceObject("Ceres", 475, 0.437, 0.95, 2.08, 0.27, "Dwarf planet"),
                new SpaceObject("Pallas", 266, 0.078, 0.211, 2.8, 0.2, "Asteroid"),
                new SpaceObject("Vesta", 264.6, 0.078, 0.262, 3.42, 0.251, "Asteroid")
            })
        };
    }
}

Program.cs

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

You can use the RowExporting event to export selected records and keep row hierarchy. Note that you need to export all parents of a selected row to display this row in the exported document (even if parents are unselected). The following example exports selected space objects and keeps hierarchy:

@rendermode InteractiveServer
@inject SpaceObjectDataProvider SpaceObjectDataProvider

<DxTreeList @ref="TreeList"
            Data="TreeListData"
            ChildrenFieldName="Satellites"
            @bind-SelectedDataItems="SelectedDataItems">
    <Columns>
        <DxTreeListSelectionColumn Width="60px" AllowSelectAll="true" />
        <DxTreeListDataColumn FieldName="Name" />
        <DxTreeListDataColumn FieldName="TypeOfObject" Caption="Type" />
        <DxTreeListDataColumn FieldName="Mass10pow21kg" Caption="Mass, kg" DisplayFormat="N2" />
        <DxTreeListDataColumn FieldName="MeanRadiusInKM" Caption="Radius, km" DisplayFormat="N2" />
    </Columns>
    <ToolbarTemplate>
        <DxToolbar>
            <DxToolbarItem Text="Export to XLSX" Click="ExportXlsx_Click" BeginGroup="true" />
        </DxToolbar>
    </ToolbarTemplate>
</DxTreeList>

@code {
    ITreeList TreeList { get; set; }
    object TreeListData { get; set; }
    IReadOnlyList<object> SelectedDataItems { get; set; }

    protected override async Task OnInitializedAsync() {
        TreeListData = SpaceObjectDataProvider.GenerateData();
    }
    async Task ExportXlsx_Click() {
        await TreeList.ExportToXlsxAsync("ExportResult", new TreeListXlExportOptions() {
            RowExporting = OnRowExporting,
        });
    }
    void OnRowExporting(TreeListRowExportingEventArgs args) {
        var spaceObject = (SpaceObject)args.DataItem;
        if (SelectedDataItems.Contains(spaceObject))
            return;
        foreach(var child in spaceObject.Satellites)
            if (SelectedDataItems.Contains(child))
                return;
            else foreach (var child2 in child!.Satellites)
                if (SelectedDataItems.Contains(child2))
                    return;
        args.Cancel = true;
    }
}

For more information about data export in the TreeList component, refer to the following topic: Export Data in Blazor TreeList.