private async Task OnBeforeExcelExport(GridBeforeExcelExportEventArgs args)
 {
     await Task.CompletedTask;

     // Loop through all columns and fix the footer aggregate values
     // Replace the default "Sum: 1234.56" text with just the decimal number
     foreach (var column in args.Columns)
     {
         if (column.HasAggregate)
         {
             // Set the number format for the column so Excel treats it as a number
             column.Aggregate.Field.Value == "MyNewValue";
         }
     }
 }

Unable to cast object of type 'Telerik.DataSource.CompositeFilterDescriptor' to type 'Telerik.DataSource.FilterDescriptor'.
System.InvalidCastException: Unable to cast object of type 'Telerik.DataSource.CompositeFilterDescriptor' to type 'Telerik.DataSource.FilterDescriptor'.
at Telerik.Blazor.Components.Common.TableGridBase`2.LoadSearchFilter(IFilterDescriptor descriptor)
at Telerik.Blazor.Components.TelerikGrid`1.SetStateInternalAsync(GridState`1 state)
at Telerik.Blazor.Components.TelerikGrid`1.InvokeOnStateInit()
at Telerik.Blazor.Components.TelerikGrid`1.OnParametersSetAsync()
at Microsoft.AspNetCore.Components.ComponentBase.CallStateHasChangedOnAsyncCompletion(Task task)
at Microsoft.AspNetCore.Components.ComponentBase.RunInitAndSetParametersAsync()
at Microsoft.AspNetCore.Components.RenderTree.Renderer.GetErrorHandledTask(Task taskToHandle, ComponentState owningComponentState)
fail: Microsoft.AspNetCore.Components.Server.Circuits.CircuitHost[111]
Unhandled exception in circuit 'MYsaCsOgfpbyHeO0xNFpA7ViPHNUC6rpc1K9eIwVR5Y'.
System.InvalidCastException: Unable to cast object of type 'Telerik.DataSource.CompositeFilterDescriptor' to type 'Telerik.DataSource.FilterDescriptor'.
at Telerik.Blazor.Components.Common.TableGridBase`2.LoadSearchFilter(IFilterDescriptor descriptor)
at Telerik.Blazor.Components.TelerikGrid`1.SetStateInternalAsync(GridState`1 state)
at Telerik.Blazor.Components.TelerikGrid`1.InvokeOnStateInit()
at Telerik.Blazor.Components.TelerikGrid`1.OnParametersSetAsync()
at Microsoft.AspNetCore.Components.ComponentBase.CallStateHasChangedOnAsyncCompletion(Task task)
at Microsoft.AspNetCore.Components.ComponentBase.RunInitAndSetParametersAsync()
at Microsoft.AspNetCore.Components.RenderTree.Renderer.GetErrorHandledTask(Task taskToHandle, ComponentState owningComponentState)

            <div style="padding: 0; width: @(ShowSidePanel ? "65%" : "99%")" tabindex="0" @onkeydown="@(OnKeyPress)">
                <TelerikGrid TItem="IncomingInvoiceGridItemViewModel"
                             @ref="GridRef"
                             Class="admin-grid"
                             Height="@OverviewHeight"
                             RowHeight="50"
                             Pageable="false"
                             PageSize="PageSize"
                             FilterMode="@GridFilterMode.FilterMenu"
                             Sortable="true"
                             Resizable="true"
                             Reorderable="true"
                             ShowColumnMenu="true"
                             ScrollMode="@GridScrollMode.Virtual"
                             SelectionMode="@GridSelectionMode.Single"
                             OnStateInit="@OnStateInit_SetStateAsync"
                             OnStateChanged="@OnStateChanged_SaveStateAsync"
                             SelectedItemsChanged="@OnSelectedItemsChanged_LoadPdf"
                             OnRead="@OnRead_UpdateFilteredItems">
                    <GridSettings>
                        <GridColumnMenuSettings Lockable="false" />
                    </GridSettings>
...
<!-- aggregates, columns and noDataTemplate omitted -->
...
                </TelerikGrid>
            </div>

<table class="table">
    <tr>
        <td class="table-active" style="width: 40px; text-align: center"><input type="checkbox" /> </td>
        <td>test</td>
    </tr>
</table>

<TelerikGrid TItem="GData" @ref="gHL" OnRead=@GReadItems OnStateInit="@OnStateGHL">
...
<GridAggregates>
@if(1==2){...}
</GridAggregates>
@code{
protected async Task GReadItems(GridReadEventArgs args)
{
	**hack for C)
	if(gHL==null)return;//state init AVOID 2x call gread PRIOR OnStateInit
...// must be called:
args.AggregateResults = rr.ToDataSourceResult(args.Request).AggregateResults;
...
}
void OnStateGHL(GridStateEventArgs<GData> args) //or async Task doesnt matter
{
//default SORTing:args.GridState = new GridState<GData>
	{
		SortDescriptors = new List<Telerik.DataSource.SortDescriptor>
	{
		new Telerik.DataSource.SortDescriptor{ Member = nameof(GData.DatPorizeni), SortDirection = Telerik.DataSource.ListSortDirection.Descending },
		//new Telerik.DataSource.SortDescriptor{ Member = nameof(GData.Skupina), SortDirection = Telerik.DataSource.ListSortDirection.Ascending }

	}
	};
}
}
	

@using Telerik.Blazor.Components.Grid

@inject IJSRuntime JS

<PageTitle>Home</PageTitle>

<TelerikGrid Data="@GridData">
    <GridToolBarTemplate>
        <TelerikButton OnClick="@ExportGridWithOtherColumns">Export Programmatically</TelerikButton>
        <GridCommandButton Class="hidden-export-button" Command="ExcelExport">Export Natively</GridCommandButton>
    </GridToolBarTemplate>
    <GridSettings>
        <GridExcelExport OnBeforeExport="@OnGridBeforeExport" />
    </GridSettings>
    <GridColumns>
        <GridColumn Field="@nameof(Product.Id)" Width="100px" />
        <GridColumn Field="@nameof(Product.Name)" Width="120px" />
        <GridColumn Title="Product Details">
            <Columns>
                <GridColumn Field="@nameof(Product.Group)" Width="180px" />
                <GridColumn Field="@nameof(Product.Price)" DisplayFormat="{0:c2}" Width="120px" />
                <GridColumn Field="@nameof(Product.Quantity)" DisplayFormat="{0:n0}" Width="120px" />
                <GridColumn Field="@nameof(Product.Released)" DisplayFormat="{0:d}" Width="180px" />
                <GridColumn Field="@nameof(Product.Discontinued)" Width="100px" />
            </Columns>
        </GridColumn>
    </GridColumns>
</TelerikGrid>

<style>
    .hidden-export-button {
        display: none;
    }
</style>

<script suppress-error="BL9992">
    function clickExportCommandButton() {
        let hiddenExportButton = document.querySelector(".hidden-export-button");
        if (hiddenExportButton) {
            hiddenExportButton.click();
        }
    }
</script>

@code {
    private List<Product> GridData { get; set; } = new();

    private void OnGridBeforeExport(GridBeforeExcelExportEventArgs args)
    {
        List<string> exportableColumnFields = new List<string> { nameof(Product.Name), nameof(Product.Price), nameof(Product.Quantity) };
        List<GridExcelExportColumn> ColumnsToExport = new();

        foreach (GridExcelExportColumn column in args.Columns)
        {
            if (exportableColumnFields.Contains(column.Field))
            {
                ColumnsToExport.Add(column);
            }
        }

        args.Columns = ColumnsToExport;
    }

    private async Task ExportGridWithOtherColumns()
    {
        await JS.InvokeVoidAsync("clickExportCommandButton");
    }

    protected override void OnInitialized()
    {
        var rnd = Random.Shared;

        for (int i = 1; i <= 7; i++)
        {
            GridData.Add(new Product()
            {
                Id = i,
                Name = $"Name {i} {(char)rnd.Next(65, 91)}{(char)rnd.Next(65, 91)}",
                Group = $"Group {i % 3 + 1}",
                Price = rnd.Next(1, 100) * 1.23m,
                Quantity = rnd.Next(0, 10000),
                Released = DateTime.Today.AddDays(-rnd.Next(60, 1000)),
                Discontinued = i % 4 == 0
            });
        }
    }

    public class Product
    {
        public int Id { get; set; }
        public string Name { get; set; } = string.Empty;
        public string Group { get; set; } = string.Empty;
        public decimal Price { get; set; }
        public int Quantity { get; set; }
        public DateTime Released { get; set; }
        public bool Discontinued { get; set; }
    }
}

<TelerikGrid Data="@GridData"
             SelectionMode="@GridSelectionMode.Multiple"
             SelectedItems="@SelectedItems"
             SelectedItemsChanged="@( (IEnumerable<Employee> newSelected) => OnSelectedItemsChanged(newSelected) )"
             Height="300px">
    <GridToolBarTemplate>
        <TelerikButton Enabled="@(SelectedItems.Any())" OnClick="@DeleteSelectedEmployees">Delete</TelerikButton>
    </GridToolBarTemplate>
    <GridColumns>
        <GridCheckboxColumn SelectAll="true" />
        <GridColumn Field="Name" Title="Name" />
        <GridColumn Field="Team" Title="Team" />
    </GridColumns>
</TelerikGrid>

@code {
    private List<Employee> GridData { get; set; } = Enumerable.Range(1, 10).Select(i => new Employee
    {
        EmployeeId = i,
        Name = $"Employee {i}",
        Team = $"Team {i % 3}"
    }).ToList();

    private List<Employee> SelectedItems { get; set; } = new();

    private void OnSelectedItemsChanged(IEnumerable<Employee> items)
    {
        SelectedItems = items.ToList();
    }

    private void DeleteSelectedEmployees()
    {
        if (SelectedItems.Any())
        {
            GridData = GridData.Except(SelectedItems).ToList();
            SelectedItems.Clear();
        }
    }

    public class Employee
    {
        public int EmployeeId { get; set; }
        public string Name { get; set; }
        public string Team { get; set; }
        public override bool Equals(object obj) => obj is Employee e && e.EmployeeId == EmployeeId;
        public override int GetHashCode() => EmployeeId.GetHashCode();
    }
}