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V24.2

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DxTreeList.SelectDataItem(Object, Boolean) Method

Selects or deselects a row that corresponds to the specified data item.

Namespace: DevExpress.Blazor

Assembly: DevExpress.Blazor.v24.2.dll

NuGet Package: DevExpress.Blazor

#Declaration

C#
public void SelectDataItem(
    object dataItem,
    bool selected = true
)

#Parameters

Name Type Description
dataItem Object

The data item.

#Optional Parameters

Name Type Default Description
selected Boolean True

true to select the row; false to deselect the row.

#Remarks

The following methods allow you to manage TreeList selection:

Pass a data item to the SelectDataItem method to select the corresponding row. The method’s behavior depends on the selection mode:

You can deselect a row in one of the following ways:

  • Call the DeselectDataItem method.
  • Call the SelectDataItem method and pass false as the second parameter.

The following example selects and deselects the row that corresponds to the first data item:

@inject EmployeeTaskService EmployeeTaskService

<DxTreeList @ref="MyTreeList"
            Data="TreeListData"
            KeyFieldName="Id"
            ParentKeyFieldName="ParentId"
            AllowSelectRowByClick="true"
            @bind-SelectedDataItems="@SelectedDataItems">
    <Columns>
        <DxTreeListDataColumn FieldName="Name" Caption="Task" />
        <DxTreeListDataColumn FieldName="EmployeeName" />
        <DxTreeListDataColumn FieldName="StartDate" />
        <DxTreeListDataColumn FieldName="DueDate" />
    </Columns>
    <ToolbarTemplate>
        <DxToolbar>
            <Items>
                <DxToolbarItem Click="() => MyTreeList.SelectDataItem(TreeListData.First())" Text="Select First Data Item" />
                <DxToolbarItem Click="() => MyTreeList.DeselectDataItem(TreeListData.First())" Text="Deselect First Data Item" />
            </Items>
        </DxToolbar>
    </ToolbarTemplate>
</DxTreeList>

@code {
    ITreeList MyTreeList { get; set; }
    List<EmployeeTask> TreeListData { get; set; }
    IReadOnlyList<object> SelectedDataItems { get; set; }

    protected override void OnInitialized() {
        TreeListData = EmployeeTaskService.GenerateData();
    }
}

For more information about selection in the TreeList component, refer to the following topic: Selection and Focus in Blazor TreeList.

See Also