Blazorise DataGrid: Aggregates

@code{
    [Inject]
    public EmployeeData EmployeeData { get; set; }
    private List<Employee> employeeList;

    protected override async Task OnInitializedAsync()
    {
        employeeList = await EmployeeData.GetDataAsync();
        await base.OnInitializedAsync();
    }

    private int totalEmployees;
    private List<Employee> employeeSummary;

    private Task OnReadData( DataGridReadDataEventArgs<Employee> e )
    {
        if ( !e.CancellationToken.IsCancellationRequested )
        {
            List<Employee> response = null;

            // this can be call to anything, in this case we're calling a fictional api
            //var response = await Http.GetJsonAsync<Employee[]>( $"some-api/employees?page={e.Page}&pageSize={e.PageSize}" );
            if ( e.ReadDataMode is DataGridReadDataMode.Virtualize )
                response = employeeList.Skip( e.VirtualizeOffset ).Take( e.VirtualizeCount ).ToList();
            else if ( e.ReadDataMode is DataGridReadDataMode.Paging )
                response = employeeList.Skip( ( e.Page - 1 ) * e.PageSize ).Take( e.PageSize ).ToList();
            else
                throw new Exception( "Unhandled ReadDataMode" );


            if ( !e.CancellationToken.IsCancellationRequested )
            {
                totalEmployees = employeeList.Count;
                employeeList = new List<Employee>( response ); // an actual data for the current page
                                                               //var aggregateResponse = await Http.GetJsonAsync<Employee[]>( $"some-aggregate-api/employees" );
                employeeSummary = employeeList; //aggregateResponse.Data
            }
        }
        return Task.CompletedTask;
    }
}