public class CIMFeatureSortInfo : CIMObject, System.ComponentModel.INotifyPropertyChanged, System.Xml.Serialization.IXmlSerializable  

{
    //Within QueuedTask.Run()
    if (featureLayer.GetIsFeatureDrawOrderSupported())
    {
        var listOfSortInfo = new List<CIMFeatureSortInfo>
        {
            //Draw features in the layer ordered by Police_Precinct field in ascending order
            //and then by Crime_rate field in descending order
            new CIMFeatureSortInfo
            {
                FieldName = "Police_Precinct",
                SortDirection = SortOrderType.Ascending
            },
            new CIMFeatureSortInfo
            {
                FieldName = "Crime_rate",
                SortDirection = SortOrderType.Descending
            }
        };
        //Provide the list of FSOs to use and their sort ordering
        //All fields must exist on the layer.
        if (featureLayer.GetCanSetFeatureDrawOrder(listOfSortInfo))
        {
            //Set the FDO to use the list of FSOs
            featureLayer.SetFeatureDrawOrder(listOfSortInfo);
        }
    }
}

{
    //Within QueuedTask.Run()
    if (featureLayer.GetIsFeatureDrawOrderSupported())
    {
        var cimFeatSortInfo = featureLayer.GetFeatureDrawOrder();
        var c = 0;
        System.Diagnostics.Debug.WriteLine("Feature Sort Info:");
        foreach (var fs_info in cimFeatSortInfo)
        {
            System.Diagnostics.Debug.WriteLine(
              $"fs_info[{c++}] {fs_info.FieldName}: {fs_info.SortDirection.ToString()}");
        }
    }
}