DataEnvelope.cs

using System;
using System.Collections.Generic;
using System.Text;
using Telerik.DataSource;

namespace CustomSerializer.Shared
{
    /// <summary>
    /// An evenlope for the DataSourceResult serialization back to the client.
    /// Needed because the framework cannot otherwise deserialize the IEnumerable collection
    /// that the Telerik DataSource package produces - it requires an explicit type -
	/// System.Text.Json cannot successfully deserialize interface properties.
    /// </summary>
    /// <typeparam name="T">The model type that is sent from the server</typeparam>
    public class DataEnvelope<T>
    {
        /// <summary>
        /// Use this when there is data grouping
        /// </summary>
        public List<AggregateFunctionsGroup> GroupedData { get; set; }

        /// <summary>
        /// Use this when there is no data grouping and the response is flat data, like in the common case.
        /// </summary>
        public List<T> CurrentPageData { get; set; }

        /// <summary>
        /// Always set this to the total number of records.
        /// </summary>
        public int TotalItemCount { get; set; }
    }
}