public sealed class MapTopologyProperties : TopologyProperties 

// Retrieves and processes the list of available topologies in the active map.
await QueuedTask.Run(async () =>
{
  var map = MapView.Active.Map;
  //Get a list of all the available topologies for the map
  var availableTopologies = await map.GetAvailableTopologiesAsync();

  var gdbTopologies = availableTopologies.OfType<GeodatabaseTopologyProperties>();
  var mapTopologies = availableTopologies.OfType<MapTopologyProperties>();
});

// Retrieves the properties of the active topology associated with the specified map asynchronously.
var activeTopologyProperties = await activeMap.GetActiveTopologyAsync();
var isMapTopology = activeTopologyProperties is MapTopologyProperties;
var isGdbTopology = activeTopologyProperties is GeodatabaseTopologyProperties;
var isNoTopology = activeTopologyProperties is NoTopologyProperties;

{
  // Retrieves the topology properties for the specified map asynchronously.
  var mapTopoProperties = await activeMap.GetTopologyAsync("Map") as MapTopologyProperties;
  var tolerance_m = mapTopoProperties.Tolerance;
  var defaultTolerance_m = mapTopoProperties.DefaultTolerance;
}

// Sets the topology of the specified map as the current map topology asynchronously.
if (activeMap.CanSetMapTopology())
{
  //Set the topology of the map as map topology
  var mapTopoProperties = await activeMap.SetMapTopologyAsync() as MapTopologyProperties;
}