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V24.2

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DxTreeList.Reload() Method

Reloads TreeList data.

Namespace: DevExpress.Blazor

Assembly: DevExpress.Blazor.v24.2.dll

NuGet Package: DevExpress.Blazor

#Declaration

C#
public void Reload()

#Remarks

The TreeList component reloads its data automatically in response to the following actions:

Observable Data Collection Notification
You can bind the TreeList to a data collection that implements the INotifyCollectionChanged or IBindingList interface. These collections notify the TreeList about changes and cause automatic updates. For more information, refer to the following help topic: Observable Data Collections.
Data Instance Change
If you change an instance of a field/property bound to the Data parameter, the TreeList reloads its data in response to this change. You can use this technique if you post updates to the underlying service (such as DbContext EF Core).
Editing-Related Events
You can allow users to edit TreeList data. To process user input and save changes, handle EditModelSaving and DataItemDeleting events. The TreeList reloads its data after the corresponding event handler is executed. For more information, refer to the following help topic: Edit Model in Blazor TreeList.

Call the Reload method after the TreeList’s bound data source is changed. The method gets updated data from the source and applies changes to the TreeList. The following sample binds the TreeList to a List<T> and removes the last item from the list on a button click:

@inject EmployeeTaskService EmployeeTaskService

<div style="margin-bottom: 10px">
    <DxButton Text="Remove Last" Click="RemoveLastItem" />
</div>

<DxTreeList @ref="MyTreeList" Data="TreeListData" KeyFieldName="Id" ParentKeyFieldName="ParentId">
    <Columns>
        <DxTreeListDataColumn FieldName="Name" Caption="Task" />
        <DxTreeListDataColumn FieldName="EmployeeName" />
        <DxTreeListDataColumn FieldName="StartDate" />
        <DxTreeListDataColumn FieldName="DueDate" />
    </Columns>
</DxTreeList>

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

    protected override void OnInitialized() {
        TreeListData = EmployeeTaskService.GenerateData();
    }
    void RemoveLastItem() {
        TreeListData.Remove(TreeListData.Last());
        MyTreeList.Reload();
    }
}

#Implements

See Also