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V24.2

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DxTreeList.ExpandRow(Int32) Method

Expands the row with the specified visible index.

Namespace: DevExpress.Blazor

Assembly: DevExpress.Blazor.v24.2.dll

NuGet Package: DevExpress.Blazor

#Declaration

C#
public void ExpandRow(
    int visibleIndex
)

#Parameters

Name Type Description
visibleIndex Int32

A row’s visible index.

#Remarks

Call the ExpandAll or CollapseAll method to expand or collapse all rows in the TreeList component. Pass a row’s visible index to the ExpandRow or CollapseRow method to expand or collapse the row. If the row does not have children, these method calls have no effect. The IsRowExpanded method returns whether a row with the specified visible index is expanded.

Note

When the TreeList is bound to the GridDevExtremeDataSource or loads data on demand, call the WaitForRemoteSourceRowLoadAsync(Int32) method before you execute the ExpandRow method to ensure that the specified data row is loaded.

Enable the AutoExpandAllNodes property to automatically expand TreeList rows when the TreeList loads data.

#Example

The following code example allows users to click rows to expand and collapse them:

@inject SpaceObjectDataProvider SpaceObjectDataProvider

<DxTreeList @ref="TreeList" Data="TreeListData" ChildrenFieldName="Satellites" RowClick="OnRowClick">
    <Columns>
        <DxTreeListDataColumn FieldName="Name" />
        <DxTreeListDataColumn FieldName="TypeOfObject" Caption="Type" />
        <DxTreeListDataColumn FieldName="Mass10pow21kg" Caption="Mass, kg" DisplayFormat="N2">
            <HeaderCaptionTemplate>Mass, 10<sup>21</sup> &#215; kg</HeaderCaptionTemplate>
        </DxTreeListDataColumn>
        <DxTreeListDataColumn FieldName="MeanRadiusInKM" Caption="Radius, km" DisplayFormat="N2"/>
        <DxTreeListDataColumn FieldName="Volume10pow9KM3" DisplayFormat="N2">
            <HeaderCaptionTemplate>Volume, 10<sup>9</sup> &#215; km<sup>3</sup></HeaderCaptionTemplate>
        </DxTreeListDataColumn>
        <DxTreeListDataColumn FieldName="SurfaceGravity" DisplayFormat="N2">
            <HeaderCaptionTemplate>Gravity, m/s<sup>2</sup></HeaderCaptionTemplate>
        </DxTreeListDataColumn>
    </Columns>
</DxTreeList>

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

    protected override async Task OnInitializedAsync() {
        TreeListData = SpaceObjectDataProvider.GenerateData();
    }

    void OnRowClick(TreeListRowClickEventArgs e) {
        if (TreeList.IsRowExpanded(e.VisibleIndex))
            TreeList.CollapseRow(e.VisibleIndex);
        else
            TreeList.ExpandRow(e.VisibleIndex);
    }
}

#Implements

See Also